Sanna F. Siddiqui, Andre Archer, Dustin Fandetti and Carl McGee
The aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight…
Abstract
Purpose
The aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight reduction savings. As such, the purpose of this study is to provide an understanding of the mechanical performance of these materials under extreme operational conditions characteristic of in-service environments.
Design/methodology/approach
This study is novel in that it has evaluated the tensile performance and fracture response of additively manufactured continuous carbon fiber embedded in an onyx matrix (i.e. nylon with chopped carbon fiber) at cryogenic and room temperatures, for specimens manufactured with an angle between the specimen lying plane and the working build plane of 0°, 45° and 90°.
Findings
Research findings reveal enhanced tensile properties (i.e. ultimate tensile strength and modulus of elasticity) by the 0° (X) built specimens, as compared with the 45° (XZ45) and 90° (Z) built specimens at cryogenic temperature. A reduction in ductility is observed at cryogenic temperature for all build orientations. Fractographic analysis reveals the presence of fiber pullout/elongation, pores within the onyx matrix and chopped carbon fiber near fracture zone of the onyx matrix.
Research limitations/implications
Research findings present tensile properties (i.e. ultimate tensile strength, modulus of elasticity and elongation%) for three-dimensional (3D)-printed onyx with and without reinforcing continuous carbon fiber composites at cryogenic and room temperatures. Reinforcement of continuous carbon fibers and reduction to cryogenic temperatures appears to result, in general, in an increase in the tensile strength and modulus of elasticity, with a reduction in elongation% as compared with the onyx matrix tensile performance reported at room temperature. Fracture analysis reveals continuous carbon fiber pull out for onyx–carbon fiber samples tested at room temperature and cryogenic temperatures, suggesting weak onyx matrix–continuous carbon fiber adhesion.
Originality/value
To the best of the authors’ knowledge, this study is the first study to report on the cryogenic tensile properties and fracture response exhibited by 3D-printed onyx–continuous carbon fiber composites. Evaluating the viability of common commercial 3D printing techniques in producing composite parts to withstand cryogenic temperatures is of critical import, for aerospace applications.
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Devotes the entire journal issue to managing human behaviour in US industries, with examples drawn from the airline industry, trading industry, publishing industry, metal products…
Abstract
Devotes the entire journal issue to managing human behaviour in US industries, with examples drawn from the airline industry, trading industry, publishing industry, metal products industry, motor vehicle and parts industry, information technology industry, food industry, the airline industry in a turbulent environment, the automotive sales industry, and specialist retailing industry. Outlines the main features of each industry and the environment in which it is operating. Provides examples, insights and quotes from Chief Executive Officers, managers and employees on their organization’s recipe for success. Mentions the effect technology has had in some industries. Talks about skilled and semi‐skilled workers, worker empowerment and the formation of teams. Addresses also the issue of change and the training that is required to deal with it in different industry sectors. Discusses remuneration packages and incentives offered to motivate employees. Notes the importance of customers in the face of increased competition. Extracts from each industry sector the various human resource practices that companies employ to manage their employees effectively ‐ revealing that there is a wide diversity in approach and what is right for one industry sector would not work in another. Offers some advice for managers, but, overall, fails to summarize what constitutes effective means of managing human behaviour.
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Nanette Monin and D. John Monin
Recognizes the link between rhetoric and organizational outcomes in organizational theory. Suggests that it is a link which could also be developed in organizational change…
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Recognizes the link between rhetoric and organizational outcomes in organizational theory. Suggests that it is a link which could also be developed in organizational change management; and that selected literary texts could provide a valid learning resource for exploring the role of root metaphors in organizational culture and in management development. Literary artists filter “real life” through a personal, but sensitively attuned conduit; so their “findings” and “conclusions” provide a challenging alternative to the traditional case study. If, for example, literary texts suggest that root metaphors in organizational culture influence action, then it would follow that management initiative to change a root metaphor could lead to change in action outcomes.
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John A. Parnell and Lewis Hershey
This study considers the viability of the combination strategy with regard to the Porter and Miles & Snow generic strategy typologies. Within each framework, it is possible to…
Abstract
This study considers the viability of the combination strategy with regard to the Porter and Miles & Snow generic strategy typologies. Within each framework, it is possible to pursue a “combination strategy,” whereby dimensions of two or more pure strategies are incorporated simultaneously. The present study presents findings from a recent assessment of perceptions of 415 American and Mexican managers regarding their firms’ strategies and levels of performance. Data suggests that combination strategies can be associated with either inferior or superior performance. This paper also suggests that additional research should considerre‐visit the I/O versus resource‐based schism and seek to integrate the two schools of thought into a broader consensus.
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Theodore S. Ransaw, Michael Lachney and Kevin K. Green
Research suggests there are at least three challenges to Black male interest and success in STEM careers: increasing access to STEM resources and curriculum, increasing Black and…
Abstract
Research suggests there are at least three challenges to Black male interest and success in STEM careers: increasing access to STEM resources and curriculum, increasing Black and male inclusiveness in STEM initiatives, and increasing cultural and technical competency in STEM fields. African American schools typically do not have equitable STEM resources or instruction. In addition, there is limited research on supporting Black males' success in STEM in the culturally responsive computing (CRC) literature. Most STEM initiatives prioritize increasing the number of girls in STEM fields. STEM field employers are not active recruiters of Black male hires and have little experience with diversity and cultural inclusiveness. Research also suggests that Black students may not be interested working in White corporate America that undervalues their unique cultural perspectives and are more concerned with schooling that improves their communities. This chapter utilized CRC as a lens to examine the complexity of engaging Black males in STEM. As a result, the authors suggest adopting an equity ethic to help teachers help Black males connect themselves and their communities to STEM technology by utilizing smartphones and smartphone technology to engage Black males who may not have access to computers. We end with an example of CRC called barbershop computing, which combines computing, engineering, and innovation as a method to attract and retain Black males in STEM classes and help them persist in STEM careers.
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William L. Waugh and Wesley W. Waugh
Phenomenologists are among the strongest opponents of logical positivism. Mostly associated with Edmund Husserl, phenomenology is essentially an analytical method or framework for…
Abstract
Phenomenologists are among the strongest opponents of logical positivism. Mostly associated with Edmund Husserl, phenomenology is essentially an analytical method or framework for describing and explaining social relationships and psychological orientations. Phenomenologists attempt to account for the subjective qualities which logical positivists and empiricists assume to be unreal or are mistakenly treated as objective observable phenomena. The authors note that phenomenology has been absorbed into the literature and the language of the field especially in terms of how people do and do not relate to bureaucratic organizations and government programs.
Elfie J. Czerny and Dominik Godat
Innovation originally meant ‘change’ or ‘renewal’. Over time, it became associated with creating new products, methods, materials, markets, and forms of organisation. Today, in…
Abstract
Innovation originally meant ‘change’ or ‘renewal’. Over time, it became associated with creating new products, methods, materials, markets, and forms of organisation. Today, in everyday language, innovation is used as a much broader term that encompasses non-materialistic, non-economical ideas such as social, educational, philosophical, political, environmental, or spiritual innovations. What makes something innovative is subjective and depends not only on the perceived novelty of the content but also on the co-constructed meaning of what is possible or what it changes in our lives. Therefore, innovation leaders must also become experts in co-constructing meanings with their teams. In this chapter, a structured solution-focused framework will be introduced with the intent to support innovative teams in maintaining effective team dialogue, foster more innovative team collaboration, better innovations, or an improved innovation process. In fostering an interactive and dynamic team process, solution-focused leaders engage in deliberate interactions that often initiate a positive dynamic leading into an even more innovative future.
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Essam Mahmoud and C. Carl Pegels
A method is developed for evaluating forecasting models withrespect to both error and complexity in forecasting. Several types offorecasting accuracy measures (MSE, MPE, MAPE…
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A method is developed for evaluating forecasting models with respect to both error and complexity in forecasting. Several types of forecasting accuracy measures (MSE, MPE, MAPE, Theil′s U‐Statistic and a loss cost function) are examined and the approach is illustrated using short‐term forecasting methods, and weekly and four‐weekly data. The approach can, however, be applied equally to immediate, medium‐ and long‐term forecasting.