Vamsi Krishna Balla, Luke B. Roberson, Gregory W. O'Connor, Steven Trigwell, Susmita Bose and Amit Bandyopadhyay
The purpose of this paper is to evaluate the feasibility of direct fabrication of lunar/Martian regolith simulant parts, in a freeform environment, using Laser Engineering Net…
Abstract
Purpose
The purpose of this paper is to evaluate the feasibility of direct fabrication of lunar/Martian regolith simulant parts, in a freeform environment, using Laser Engineering Net Shaping (LENS™) – an additive manufacturing technology.
Design/methodology/approach
Bulk lunar regolith simulant structures were fabricated using a LENS™‐750. Dense parts without any macroscopic defects were produced at a laser power of 50W, a scan speed of 20 mm/s, and a powder feed rate of 12.36 g/min. The laser processed parts were characterized using X‐ray diffraction, differential scanning calorimetry, scanning electron microscope and X‐ray photoelectron spectroscopy to evaluate the influence of laser processing on the microstructure, constituent phases and chemistry of lunar regolith simulant.
Findings
A combination of laser parameters resulting in a 2.12 J/mm2 laser energy appeared to be ideal for generating a melt pool necessary for lunar regolith powder deposition without excessive liquid pool spreading and cracking of solidified parts. The results show that LENS™ based laser processing transformed crystalline regolith into nanocrystalline and/or amorphous regolith structures as a result of complete melting followed by resolidification. Laser processing also resulted in marginal changes in the composition of the regolith.
Originality/value
Establishment of a lunar/Martian outpost necessitates the development of methods to utilize in situ mineral resources for various construction and resource extraction applications. Fabrication technologies are critical for habitat structure development, as well as repair and replacement of tools and parts at the outpost. Current experimental results presented in the paper clearly demonstrate that net shape regolith simulant parts can be fabricated using LENS™ by exploiting its capabilities.
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DUBLIN DID NOT LACK literary talent in 1924. When Francis Stuart, his wife Iseult, and Cecil Salkeld decided to bring out a new periodical devoted to the arts, they found little…
Abstract
DUBLIN DID NOT LACK literary talent in 1924. When Francis Stuart, his wife Iseult, and Cecil Salkeld decided to bring out a new periodical devoted to the arts, they found little difficulty collecting material. W. B. Yeats and Joseph Campbell contributed poems, Liam O'Flaherty a short story. Lennox Robinson—dramatist, director of the Abbey Theatre and secretary of the Carnegie United Kingdom Trust's Irish office—was too busy to write anything specially, but offered a story written years previously in New York, ‘The Madonna of Slieve Dun’. The first issue of To‐morrow: a New Irish Monthly (price sixpence) appeared in August. Within six months the Carnegie Trust's Irish Advisory Committee was suspended and Robinson, its secretary, dismissed.
At a recent inquest upon the body of a woman who was alleged to have died as the result of taking certain drugs for an improper purpose, one of the witnesses described himself as…
Abstract
At a recent inquest upon the body of a woman who was alleged to have died as the result of taking certain drugs for an improper purpose, one of the witnesses described himself as “an analyst and manufacturing chemist,” but when asked by the coroner what qualifications he had, he replied : “I have no qualifications whatever. What I know I learned from my father, who was a well‐known ‘F.C.S.’” Comment on the “F.C.S.” is needless.
Charlotte Ryan and Gregory Squires
We argue that by conducting systematic research with communities rather than on communities, community-based research (CBR) methods can both advance the study of human interaction…
Abstract
We argue that by conducting systematic research with communities rather than on communities, community-based research (CBR) methods can both advance the study of human interaction and strengthen public understanding and appreciation of social sciences. CBR, among other methods, can also address social scientists’ ethical and social commitments. We recap the history of calls by leading sociologists for rigorous, empirical, community-engaged research. We introduce CBR methods as empirically grounded methods for conducting social research with social actors. We define terms and describe the range of methods that we include in the umbrella term, “community-based research.” After providing exemplars of community-based research, we review CBR’s advantages and challenges. We, next, summarize an intervention that we undertook as members of the Publication Committee of the URBAN Research Network’s Sociology section in which the committee developed and disseminated guidelines for peer review of community-based research. We also share initial responses from journal editors. In the conclusion, we revisit the potential of community-based research and note the consequences of neglecting community-based research traditions.
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This paper synthesizes the extant feedback literature, focusing on how feedback affects an auditor’s learning, performance, and motivation. Performance feedback is an important…
Abstract
This paper synthesizes the extant feedback literature, focusing on how feedback affects an auditor’s learning, performance, and motivation. Performance feedback is an important component in the auditing environment for ensuring quality control and for developing and coaching staff auditors. However, the literature on feedback in the audit environment is fragmented and limited making it difficult to assess its behavioral effects on auditors. This paper has three main objectives. The first is to review some of the influential research in psychology and management to identify key variables and issues that appear to be critical in the study of behavioral consequences of feedback in organizational settings. The second is to review performance feedback research specifically in auditing to identify the areas previously examined and synthesize the findings. The third is to suggest a variety of future research opportunities that may assist in developing an understanding and knowledge of the behavioral effects of feedback on auditors. The literature analysis has significant implications for audit research and practice. In particular, the analysis provides important insights into understanding who, how, and when performance feedback should be given to improve its effectiveness in the audit environment.
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Jean Clarke and Mark P. Healey
We argue that voice – the sound that people produce when they speak – is an important resource for entrepreneurs, especially when they are pitching to potential investors. We…
Abstract
We argue that voice – the sound that people produce when they speak – is an important resource for entrepreneurs, especially when they are pitching to potential investors. We integrate evidence from entrepreneurship, social psychology and linguistics to show that the voice can be regarded both as a tool for entrepreneurs to utilize and as a vital source of information allowing listeners to make judgements about the speaker and their message. To better understand how the voice may be used and interpreted in investment pitches, we develop a model of the relationship between the entrepreneurial voice and investor judgments. Voice depends on entrepreneurs’ characteristics including gender and communication goals but can be utilized to express emotions (purposefully or not) and signal qualities such as competence and trustworthiness. How potential investors interpret these displays depends on cultural expectations and stereotypes. Our review illustrates that female entrepreneurs may find it more difficult to persuade investors due to their naturally higher voice pitch and bias against speech patterns prevalent among young women. We highlight directions for future research exploring the voice as a unique cultural resource for entrepreneurs.
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THE topics of the Library Association Conference and the election of the Council of the Association naturally absorb a great deal of attention this month. To deal with the second…
Abstract
THE topics of the Library Association Conference and the election of the Council of the Association naturally absorb a great deal of attention this month. To deal with the second first: there were few novelties in the nominations, and most of the suggested new Councillors are good people; so that a fairly good Council should result. The unique thing, as we imagine, about the Library Association is the number of vice‐presidents, all of whom have Council privileges. These are not elected by the members but by the Council, and by the retiring Council; they occupy a position analagous to aldermen in town councils, and are not amenable to the choice or desires of the members at large. There are enough of them, too, if they care to be active, to dominate the Council. Fortunately, good men are usually elected, but recently there has been a tendency to elect comparatively young men to what are virtually perpetual seats on the Council, simply, if one may judge from the names, because these men occupy certain library positions. It, therefore; is all the more necessary that the electors see that men who really represent the profession get the seats that remain.