Daniel A. Porter, Nicholas Davis, Paul S. Krueger, Adam L. Cohen and David Son
Techniques of extrude and cure additive manufacturing for thermally cured, high viscosity and medical-grade silicone are investigated by using a small ram extruder and a…
Abstract
Purpose
Techniques of extrude and cure additive manufacturing for thermally cured, high viscosity and medical-grade silicone are investigated by using a small ram extruder and a near-infrared (IR) laser. The purpose of this study is to evaluate the process parameter effects on the stiffness of the final products.
Design/methodology/approach
Process parameter effects on axial stiffness values and durometer are explored. Parameters such as extrusion layer height, laser speed, laser current, laser raster spacing and multiple laser passes were investigated and compared to traditional cast and cure methods. Dimensional changes were also recorded and compared.
Findings
Tensile and durometer tests show that certain curing parameters give tensile stress and durometers within 10 per cent of bulk material specifications at 200 per cent strain. Parameters that had the highest impact on tensile stress at 200 per cent strain were layer height (0.73 per cent) followed by laser power (0.69 per cent), and then laser raster spacing (0.45 per cent). Parameters that had the highest impact on durometer were laser power (1.00 per cent), followed by layer height, (0.34 per cent) and then laser raster speed (0.32 per cent). Three-dimensional printed samples had about 11.2 per cent more shrinkage than the bulk cast samples in the longest dimension.
Originality/value
This paper is one of the first that demonstrates near IR laser curing parameter effects on three-dimensional printed, commercial off-the-shelf, medical-grade and viscous silicone. The ability to cure very viscous thermosets locally enables interesting technologies such as wire encapsulation, high voltage actuators and drug delivery devices.
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A collection of essays by a social economist seeking to balanceeconomics as a science of means with the values deemed necessary toman′s finding the good life and society enduring…
Abstract
A collection of essays by a social economist seeking to balance economics as a science of means with the values deemed necessary to man′s finding the good life and society enduring as a civilized instrumentality. Looks for authority to great men of the past and to today′s moral philosopher: man is an ethical animal. The 13 essays are: 1. Evolutionary Economics: The End of It All? which challenges the view that Darwinism destroyed belief in a universe of purpose and design; 2. Schmoller′s Political Economy: Its Psychic, Moral and Legal Foundations, which centres on the belief that time‐honoured ethical values prevail in an economy formed by ties of common sentiment, ideas, customs and laws; 3. Adam Smith by Gustav von Schmoller – Schmoller rejects Smith′s natural law and sees him as simply spreading the message of Calvinism; 4. Pierre‐Joseph Proudhon, Socialist – Karl Marx, Communist: A Comparison; 5. Marxism and the Instauration of Man, which raises the question for Marx: is the flowering of the new man in Communist society the ultimate end to the dialectical movement of history?; 6. Ethical Progress and Economic Growth in Western Civilization; 7. Ethical Principles in American Society: An Appraisal; 8. The Ugent Need for a Consensus on Moral Values, which focuses on the real dangers inherent in there being no consensus on moral values; 9. Human Resources and the Good Society – man is not to be treated as an economic resource; man′s moral and material wellbeing is the goal; 10. The Social Economist on the Modern Dilemma: Ethical Dwarfs and Nuclear Giants, which argues that it is imperative to distinguish good from evil and to act accordingly: existentialism, situation ethics and evolutionary ethics savour of nihilism; 11. Ethical Principles: The Economist′s Quandary, which is the difficulty of balancing the claims of disinterested science and of the urge to better the human condition; 12. The Role of Government in the Advancement of Cultural Values, which discusses censorship and the funding of art against the background of the US Helms Amendment; 13. Man at the Crossroads draws earlier themes together; the author makes the case for rejecting determinism and the “operant conditioning” of the Skinner school in favour of the moral progress of autonomous man through adherence to traditional ethical values.
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Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely…
Abstract
Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.
Noel Scott, Brent Moyle, Ana Cláudia Campos, Liubov Skavronskaya and Biqiang Liu
Nana Y. Amoah, Isaac Bonaparte, Ebenezer K. Lamptey and Muni Kelly
Using the L. Bebchuk, Cohen, and Ferrell (2009) entrenchment index (E-index), the authors examine the relation between management entrenchment and the probability of a firm being…
Abstract
Using the L. Bebchuk, Cohen, and Ferrell (2009) entrenchment index (E-index), the authors examine the relation between management entrenchment and the probability of a firm being implicated in the stock option backdating scandal. The authors conduct the analysis of this study using logistic regression, and they document a negative relation between the E-index and the probability of a firm being implicated in the stock option backdating scandal. The results of this study are consistent with the view that management entrenchment is advantageous to shareholders as it protects managers from short-term reporting pressures and egregious opportunistic behavior that can be detrimental to firm value.
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Nancy Adam-Turner, Dana Burnett and Gail Dickinson
Technology is integral to contemporary life; where the digital transformation to virtual information accessibility impacts instruction, it alters the skills of learning and…
Abstract
Technology is integral to contemporary life; where the digital transformation to virtual information accessibility impacts instruction, it alters the skills of learning and comprehension (Gonzalez-Patino & Esteban-Guitart, 2014; Lloyd, 2010). Although librarians/media specialists provide orientation, instruction, and research methods face-to-face and electronically, they recognize that digital learning instruction is not a linear process, and digital literacy (DL) is multi-disciplinary (Belshaw, 2012). Policy and public research findings indicate that higher education must be prepared to adapt to rapid changes in digital technology (Maybee, Bruce, Lupton, & Rebmann, 2017). Digital learning undergoes frequent transformations, with new disruptive innovation and research attempts at redefinition (Palfrey, 2015). Research often overlooks junior/community colleges. We are all learners and we need to understand the digital learning challenges that incorporating DL includes in the new digital ecology (Adams Becker et al., 2017). This study provides real faculty/librarian commentaries regarding the understanding needed to develop digital learning and contemporary digital library resources. The authors investigate faculties’ and librarians’ degree of DL perceptions with instruction at junior/community colleges. Survey data analysis uses the mean of digital self-efficacy of variables collected, revealing that participants surpassed Rogers’s (2003) chasm of 20% inclusion. Findings provided data to develop the Dimensions of Digital Learning rubric, a new evaluation tool that encourages faculty DL cross-training, librarians’ digital learning collaboration, and effective digital learning spaces.
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Asya Draganova and Shane Blackman
The term Canterbury Sound emerged in the late 1960s and early 1970s to refer to a signature style within psychedelic and progressive rock developed by bands such as Caravan and…
Abstract
The term Canterbury Sound emerged in the late 1960s and early 1970s to refer to a signature style within psychedelic and progressive rock developed by bands such as Caravan and Soft Machine as well as key artists including Robert Wyatt and Kevin Ayers. This chapter explores Canterbury as a metaphor and reality, a symbolic space of music inspiration which has produced its distinctive ‘sound’.
Drawing on ethnographic fieldwork, particularly observations and interviews with music artists and cultural intermediates (Bourdieu, 1993), we suggest that the notion of the Canterbury Sound – with its affinity for experimentation, distinctive chord progressions and jazz allusions in a rock music format – is perceived as a continuing artistic and aesthetic influence. We interpret the genealogy of the Canterbury Sound alternativity through discussions focused on the position of the ‘Sound’ within contemporary heritage discourses, the metaphorical and geographical implications of place in relation to popular music, and cultural longevity of the phenomenon.