Frances D. Bryant, Guanghua Sui and Ming C. Leu
Rapid freeze prototyping is a relatively new solid freeform fabrication process, which builds a three‐dimensional part according to a CAD model by depositing and freezing water…
Abstract
Rapid freeze prototyping is a relatively new solid freeform fabrication process, which builds a three‐dimensional part according to a CAD model by depositing and freezing water droplets layer by layer. A study on the effects of RFP process parameters including the nozzle scanning speed, droplet size, and droplet frequency in building ice parts with a single‐nozzle work head is made. Presented in this paper are the results of this study which indicate that these process parameters determine the ice layer thickness and ice line width, which in turn determine the surface roughness and the waiting time required after depositing each layer of water (i.e. between successive layers) during the ice part building process.
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Frances D. Bryant and Ming C. Leu
The purpose of this paper is to develop a physics‐based model that can predict how a main build material of water interacts with a water‐soluble sacrificial support material in…
Abstract
Purpose
The purpose of this paper is to develop a physics‐based model that can predict how a main build material of water interacts with a water‐soluble sacrificial support material in the rapid freeze prototyping (RFP) process.
Design/methodology/approach
RFP uses water freezing into ice in a layer‐by‐layer manner as a main build material to create ice structures with complex geometries in a sufficiently cool environment. A eutectic dextrose‐water solution is used as a sacrificial support material. The supported areas in an ice structure are removed by placing the fabricated structure in an environment of appropriate temperature.
Findings
Two methods of concentration modeling have been developed to predict the interaction between the main and support materials around their interface region. The two models are described in detail and their predictions are compared to experimentally measured data. The experimental height data compared to the simulation result based on the concentration models agrees to within 6 percent for various build ambient temperatures. As ambient temperatures decreased, diffusion between the two materials also decreased.
Originality/value
The results obtained from this paper can be used as an aid in building complex ice parts in the RFP process so that minimal interaction between the main and support materials can be attained. An understanding of the interaction occurring during fabrication is provided with the concentration models. The method used to develop the concentration models can be applied to other layered manufacturing processes when using two miscible materials.
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Jacques Abou Khalil, César Jiménez Navarro, Rami El Jeaid, Abderahmane Marouf, Rajaa El Akoury, Yannick Hoarau, Jean-François Rouchon and Marianna Braza
This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to…
Abstract
Purpose
This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 106, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.
Design/methodology/approach
This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.
Findings
This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.
Originality/value
This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.
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Mary Vigier and Michael Bryant
The purpose of this paper is to explore the contextual and linguistic challenges that French business schools face when preparing for international accreditation and to shed light…
Abstract
Purpose
The purpose of this paper is to explore the contextual and linguistic challenges that French business schools face when preparing for international accreditation and to shed light on the different ways in which experts facilitate these accreditation processes, particularly with respect to how they capitalize on their contextual and linguistic boundary-spanning competences.
Design/methodology/approach
The authors interviewed 12 key players at four business schools in France engaged in international accreditations and in three specific categories: senior management, tenured faculty and administrative staff. The interview-based case study design used semi-structured questions and an insider researcher approach to study an underexplored sector of analysis.
Findings
The findings suggest that French business schools have been particularly impacted by the colonizing effects of English as the mandatory language of the international accreditation bodies espousing a basically Anglophone higher education philosophy. Consequently, schools engage external experts for their contextual and linguistic boundary-spanning expertise to facilitate accreditation processes.
Originality/value
The authors contribute to language-sensitive research through a critical perspective on marginalization within French business schools due to the use of English as the mandatory lingua franca of international accreditation processes and due to the underlying higher-education philosophy from the Anglophone academic sphere within these processes. As a result, French business schools resort to external experts to mediate their knowledge and competency gaps.
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We school administrators, like “practical” men everywhere, claim to have little use for theory. In this we delude ourselves, for we all theorize. The real distinction lies not…
Abstract
We school administrators, like “practical” men everywhere, claim to have little use for theory. In this we delude ourselves, for we all theorize. The real distinction lies not between theory and practice, but between good theory and bad theory. Good theory is a hypothesis which has undergone verification and which has potential for explaining and predicting events, and for the production of new knowledge. The development of theory, with its constant demand for semantic accuracy and simplicity, is essential as a guide to research, and as a guide to action (e.g. in administration) where it should be regarded as a relational map rather than as an itinerary. The work of Halpin, Guba and Getzels, for example, illustrates that no theory is likely to be the theory. The development of a science of administration is dependent upon such theories. The alchemist described his observations in a half‐mythical language full of metaphors and allegories, not In scientific concepts. Today we appear to live only in an age of educational alchemy.
Studies have shown that doctoral students are at risk of mental health issues that result from the demands and workload in doctoral programs, poor work relationships with…
Abstract
Studies have shown that doctoral students are at risk of mental health issues that result from the demands and workload in doctoral programs, poor work relationships with supervisors, and delays in graduation. Research also shows that savoring good moments can help individuals maintain and foster their wellbeing. Drawing on data from a larger phenomenological research study (Al Makhamreh, 2019), this chapter presents a discussion of the importance of savoring for wellbeing based on findings from 19 doctoral students in Canadian universities. Findings demonstrate that numerous students were able to face the challenges in their doctoral programs by savoring happy moments that benefited their wellbeing and fueled their energy to keep going to achieve their goals. Recommendations for universities include offering students courses, training, interventions, and workshops on savoring and positive psychology in general. Additionally, providing savoring outlets and opportunities (e.g., gardens and gardening activities) could help students maximize their program experiences and satisfaction.
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Leadership is basically about influence and ability to cultivate followership. This chapter examined the nature of indigenous socio-political leadership in Africa using Zimbabwe…
Abstract
Leadership is basically about influence and ability to cultivate followership. This chapter examined the nature of indigenous socio-political leadership in Africa using Zimbabwe, Sudan and Nigeria as caselets and compared this with the post-colonial or modern-day leadership realities. A survey was conducted among senior executives at Lagos Business School, Nigeria, with a sample size of 200 persons, to find out their perception of the African indigenous leadership system. An overwhelming 90% believe that culture plays a big role in shaping African leadership style. However, two-thirds of the respondents agreed that Africa lacks proper institutional structures to support good leadership, thus encouraging corruption (97% of the respondents) and non-accountability among the leaders. Also, only 5% thought cultural orientation was the reason why the African followers do not hold their leaders accountable. In other words, it is not in the African culture not to hold leaders accountable for their actions. So, what went wrong? We attempted a deeper look at the effect of colonial rule and the attendant militarisation of the African continent. Our conclusion is that the colonisation of the continent by Europe brought significant distortion to the traditional African indigenous leadership institutions and the psyche of the African leader and the followers alike. Post-colonial Africa has witnessed 133 recorded coups d’etat between 1952 and 2016. This chapter is recommended to all those who seek a deeper understanding of the nature of the African indigenous leadership practices and the factors that have shaped these over the years.
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Andres Ramirez and Joan Lofgren
Finance is a male-dominated field of work. This study aims to understand if learning in finance follows the same pattern. Furthermore, the authors want to understand if foreign…
Abstract
Purpose
Finance is a male-dominated field of work. This study aims to understand if learning in finance follows the same pattern. Furthermore, the authors want to understand if foreign female students are subject to the same cultural norms and sorting mechanisms as their counterparts from the USA or Finland.
Design/methodology/approach
In the context of a capstone course, students of two well-known international business programs (one in the USA, the other in Finland) participate in a business simulation. The authors surveyed the students on their learning experience across different business functions. The authors collected 440 responses over five years.
Findings
A gender gap exists in learning finance. Females surveyed reported learning less (9%–15%) than males. However, foreign females reported learning more (11%–17%). Additionally, the authors find no gender gap in learning of other business functions (i.e. marketing and strategy). Foreign females seem to bypass traditional roles and sorting mechanisms.
Originality/value
To the best of the authors’ knowledge, this study is the first to document the moderating effect of foreignness on the gender gap in learning.
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Michael Bryant and Robert F. Scherer
A key factor in achieving initial AACSB accreditation is establishing an effective relationship between the mentor and the business school. If individual issues are not addressed…
Abstract
A key factor in achieving initial AACSB accreditation is establishing an effective relationship between the mentor and the business school. If individual issues are not addressed during the development and implementation of the accreditation plan, time to initial accreditation can be increased substantially. We review four steps in the initial accreditation process and identify seven challenges to the mentor‐business school relationship. Strategies for meeting these challenges are developed for both mentors and business schools. General principles from the organizational mentoring literature are applied to the initial accreditation process to maximize and enhance interaction between mentors and business schools.