Peter G. Kelly, Benjamin H. Gallup and Joseph D. Roy-Mayhew
Many additively manufactured parts suffer from reduced interlayer strength. This anisotropy is necessarily tied to the orientation during manufacture. When individual features on…
Abstract
Purpose
Many additively manufactured parts suffer from reduced interlayer strength. This anisotropy is necessarily tied to the orientation during manufacture. When individual features on a part have conflicting optimal orientations, the part is unavoidably compromised. This paper aims to demonstrate a strategy in which conflicting features can be functionally separated into “co-parts” which are individually aligned in an optimal orientation, selectively reinforced with continuous fiber, printed simultaneously and, finally, assembled into a composite part with substantially improved performance.
Design/methodology/approach
Several candidate parts were selected for co-part decomposition. They were printed as standard fused filament fabrication plastic parts, parts reinforced with continuous fiber in one plane and co-part assemblies both with and without continuous fiber reinforcement (CFR). All parts were loaded until failure. Additionally, parts representative of common suboptimally oriented features (“unit tests”) were similarly printed and tested.
Findings
CFR delivered substantial improvement over unreinforced plastic-only parts in both standard parts and co-part assemblies, as expected. Reinforced parts held up to 2.5x the ultimate load of equivalent plastic-only parts. The co-part strategy delivered even greater improvement, particularly when also reinforced with continuous fiber. Plastic-only co-part assemblies held up to 3.2x the ultimate load of equivalent plastic only parts. Continuous fiber reinforced co-part assemblies held up to 6.4x the ultimate load of equivalent plastic-only parts. Additionally, the thought process behind general co-part design is explored and a vision of simulation-driven automated co-part implementation is discussed.
Originality/value
This technique is a novel way to overcome one of the most common challenges preventing the functional use of additively manufactured parts. It delivers compelling performance with continuous carbon fiber reinforcement in 3D printed parts. Further study could extend the technique to any anisotropic manufacturing method, additive or otherwise.
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This chapter assesses authentic leadership and finds it to be highly egalitarian, meaning that it may be unattractive to managers accustomed to a hierarchical style. In general…
Abstract
This chapter assesses authentic leadership and finds it to be highly egalitarian, meaning that it may be unattractive to managers accustomed to a hierarchical style. In general, management may lack knowledge about leadership theory relevant to both hierarchy and egality, the latter of which many younger employees prefer. Such a disconnect between management and follower preferences may explain two concerning findings by Gallup regarding global employee engagement: levels have remained low for nearly a decade, and companies resist Gallup's recommended cultural change. The author's ComPILAR model of group dynamics, which incorporates both egalitarian and hierarchical extremes offers potential hierarchical additions to authentic leadership, which may boost the ability of authentic leadership to guide leaders in hierarchical teams and organisations.
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Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these…
Abstract
Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these shortages are very real and quite severe.
This paper poses the question of whether the mainstream feminist movement in the United States, in concentrating its efforts on achieving gender parity in the existing workplace…
Abstract
This paper poses the question of whether the mainstream feminist movement in the United States, in concentrating its efforts on achieving gender parity in the existing workplace, is selling women short. In it, I argue that contemporary U.S. feminism has not adequately theorized the problems with the relatively unregulated market system in the United States. That failure has contributed to a situation in which women’s participation in the labor market is mistakenly equated with liberation, and in which other far-ranging effects of the market system on women’s lives inside and outside of work – many of them negative – are overlooked. To theorize the effects of the market system on women’s lives in a more nuanced manner, I borrow from the insights of earlier Marxist and socialist feminists. I then use this more nuanced perspective to outline an agenda for feminism, which I call “market-cautious feminism,” that seeks to regulate the market to serve women’s interests.
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Benjamin Valdez, Michael Schorr, Margarito Quintero, Monica Carrillo, Roumen Zlatev, Margarita Stoytcheva and Juan de Dios Ocampo
The aim of this work is to study the corrosion and scaling factors, mechanisms and processes affecting the materials, equipment and installations of the Cerro Prieto geothermal…
Abstract
Purpose
The aim of this work is to study the corrosion and scaling factors, mechanisms and processes affecting the materials, equipment and installations of the Cerro Prieto geothermal field (GTF).
Design/methodology/approach
The physicochemical characteristics of the geothermal well and fluids were analysed, recorded and related to the corrosion and scaling phenomena.
Findings
The high temperature and salinity of the steam‐brine mixture and the presence of hydrogen sulphide and carbon dioxide impart a severe level of corrosivity.
Originality/value
Corrosion and scaling control assure an efficient production regime, provide for the durability of the GTF engineering materials and equipment and contribute to environmental quality.
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The effect of government on our lives is evident when we read newspapers or magazines, watch television or listen to the radio. At the international, national, and local level…
Abstract
The effect of government on our lives is evident when we read newspapers or magazines, watch television or listen to the radio. At the international, national, and local level, decisions are made which ultimately affect many people. To understand the way governments work, political scientists study the principles, processes, and structures of government as well as the political institutions that have developed. This entails a broad range of interests because of the multiplicity and complexity of relations among governments at all levels.