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Additive manufacturing (AM) processes involve a layer-by-layer sintering of metallic powders to produce fully functional three-dimensional parts. This layer-by-layer building process provides a unique opportunity to enhance mechanical properties by applying treatments that previously were possible only on the surface in traditional manufacturing techniques. The purpose of the study is to examine the effect of ultrasonic peening (UP) applied during a layer-by-layer direct metal laser sintering (DMLS) fabrication of 316L stainless steel on its mechanical properties and microstructure.

Uniaxial tensile tests were performed at 1.27 mm/s to determine the effect of UP treatment on the average global behavior of a 316L part, whereas hardness measurements using nanoindentation were performed to determine the modification of local mechanical properties. Compressive buckling tests at a loading rate of 3 mm/min were performed on sample coupons with a large aspect ratio to evaluate the effect of UP on any potential delamination of DMLS layers. Techniques such as optical and scanning electron microscopy (SEM) imaging were utilized to determine the effect of UP on the microstructure.

Overall, significant modification in mechanical properties such as hardness and yield strength, along with microstructure, was observed. Large increases in both the average global and local mechanical properties, as well as a disruption in the columnar grain microstructure, was observed in DMLS parts treated with UP treatment.

Results indicate an opportunity for UP to be used as an in-situ process during AM processes for dynamically altering the mechanical behavior, microstructure, and distortion due to residual stress formation, in a tunable fashion.

The purpose of this paper is to identify unique Victorian-Era collections of British and American missionary activity, which provide an introduction to the breadth and depth of primary sources in the field of missiology.

This article provides a list of physical archives, digital repositories, microfilm collections and subscription databases with relevance to missionary activity in the Victorian Era. Collections were purposefully selected based on denominational importance or historical relevance. The bibliography consists of collections from both the USA and Great Britain.

Through grants from the National Endowment for the Humanities, the Andrew W. Mellon Foundation, the digital availability of Victorian Era missionary materials has increased significantly over the past decade.

This bibliography includes archival collections housed or hosted in the USA and Great Britain. The annotations describe the scope and uniqueness of each archive, and will be of interest to scholars interested in the field of missiology.

The following classified, annotated list of titles is intended to provide reference librarians with a current checklist of new reference books, and is designed to supplement the RSR review column, “Recent Reference Books,” by Frances Neel Cheney. “Reference Books in Print” includes all additional books received prior to the inclusion deadline established for this issue. Appearance in this column does not preclude a later review in RSR. Publishers are urged to send a copy of all new reference books directly to RSR as soon as published, for immediate listing in “Reference Books in Print.” Reference books with imprints older than two years will not be included (with the exception of current reprints or older books newly acquired for distribution by another publisher). The column shall also occasionally include library science or other library related publications of other than a reference character.

Violence as a foundational element of police work is continuously reaffirmed and justified through police labour as ‘violence workers’ (Seigel, 2018). Hiring more female police officers has recently been seen as a way to reduce police violence. However, would employing more female officers change the relationship between policing and violence? Arguments in favour of more female police tend to rely on stereotypical understandings of gender, emphasising that women are naturally less aggressive and more likely to be caring and compassionate, often obscuring the violence enacted by female police officers in doing so. Female officers may be more likely to engage in violence out of necessity due to police culture and occupational norms around the use of force. Examining female police across countries such as the United States, Nigeria and Slovenia, this chapter establishes female police violence as a broader pattern, reflects on how female officers participate in police violence and addresses the extent to which masculinised police culture structures the expression of police violence. This chapter concludes with a discussion of why hiring more female police officers is not an adequate solution for reducing police violence, as police officers enact and are complicit in violence, regardless of gender.

Elton Mayo was a professor at a prestigious university, but not a researcher; a scholar, but more concerned with executives; a capitalist, but someone who downplayed monetary incentives; an insider, but someone whose own background was more of an outsider. These contradictions have resulted in scholars questioning Mayo’s impact on the field of management. Thus, this paper aims to critically review Mayo and his contributions to management through a lens calibrated to the context of his time, providing a more contextually accurate view of Mayo and his work and offering a clearer view of his meaningful impact on the field.

Using a combination of primary and secondary sources, the authors connect otherwise disparate information to critically review Mayo’s work within the context of its era.

The authors’ critical review of Mayo identified nine topical areas where Mayo and/or his work have been misunderstood or misinterpreted. For each area, the authors offer a more contextualized and appropriate interpretation of Mayo and his viewpoints, and thus more accurately informing the management literature.

This paper is the first to thoroughly revisit Mayo and his work through a contextualized lens, offering a more informed view of why Mayo’s seemingly controversial behaviors were actually quite standard behaviors given his context.

In a dynamic environment where underlying competition is “for the market,” this chapter examines what happens when entrants and incumbents can instead negotiate for the market. For instance, this might arise when an entrant innovator can choose to license to or be acquired by an incumbent firm (i.e., engage in cooperative commercialization). It is demonstrated that, depending upon the level of firms’ potential dynamic capabilities, there may or may not be gains to trade between incumbents and entrants in a cumulative innovation environment; that is, entrants may not be adequately compensated for losses in future innovative potential. This stands in contrast to static analyses that overwhelmingly identify positive gains to trade from such cooperation.

It is well-known and documented that despite a plethora of efforts by institutions to broaden participation in engineering, the representation, retention, and degree completion of Black males in engineering continues to lag. Coupled with a lack of representation, there is also a dearth of research that has sought to understand the experiences of Black males in engineering. In this chapter, through the lens of Hildegard Peplau's (1991) interpersonal relations theory, we sought to explore the experiences of nine undergraduate Black male engineering majors with academic advisors. Academic advisors are strategically positioned in higher education settings as guides to help students navigate college culture, policies, and procedures. Using thematic analysis, three salient themes emerged: “spots are limited,” building their own “advising team,” and prescriptive perceptions. As institutions imagine routes for broadening participation in engineering, they might also consider how they support advisors and encourage relationship development between students and advisors.

Volume 25 celebrates the 25th year of publication for the American Journal of Business (AJB). Launched by eight MAC schools of business in March 1986, the Journal has featured more than 700 authors who have contributed more than 330 research articles at the intersection of theory and practice. From accounting to marketing, management to finance, the Journal prominently covers the breadth of the business disciplines as a general business outlet intended for both practitioners and academics. As the Journal reaches out beyond the MAC in sponsorship, authorship, and readership, we assess the Journal’s first quarter century of impact.

This paper aims to characterize the mineral composition of Martian surfaces based on Thermal Emission Spectrometer (TES; Mars Global Surveyor) as measured in the infrared thermal range. It presents modeling and interpreting of TES spectral data from selected Martian regions from which the atmospheric influences had been removed using radiative transfer algorithm and deconvolution algorithm. The spectra from the dark area of Cimmeria Terra and the bright Isidis Planitia were developed in Philip Christensen’s and Joshua Bandfield’s publications, where these spectra were subjected to spectral deconvolution to estimate the mineral composition of the Martian surface. The results of the analyses of these spectra were used for the modeling of dusty and non-dusty surface of Mars. As an additional source, the mineral compositions of Polish basalts and mafic rocks were used for these surfaces as well as for modeling Martian meteorites Shergottites, Nakhlites and Chassignites. Finally, the spectra for the modeling of the Hellas region were obtained from the Planetary Fourier Spectrometer (PFS) – (Mars Express) and the mineralogical compositions of basalts from the southern part of Poland were used for this purpose. The Hellas region was modeled also using simulated Martian soil samples Phyllosilicatic Mars Regolith Simulant and Sulfatic Mars Regolith Simulant, showing as a result that the composition of this selected area has a high content of sulfates. Linear spectral combination was chosen as the best modeling method. The modeling was performed using PFSLook software written in the Space Research Centre of the Polish Academy of Sciences. Additional measurements were made with an infrared spectrometer in thermal infrared spectroscopy, for comparison with the measurements of PFS and TES. The research uses a kind of modeling that successfully matches mineralogical composition to the measured spectrum from the surface of Mars, which is the main goal of the publication. This method is used for areas where sample collection is not yet possible. The areas have been chosen based on public availability of the data.

The infrared spectra of the Martian surface were modeled by applying the linear combination of the spectra of selected minerals, which then are normalized against the measured surface area with previously separated atmosphere. The minerals for modeling are selected based on the expected composition of the Martian rocks, such as basalt. The software used for this purpose was PFSLook, a program written in C++ at the Space Research Centre of the Polish Academy of Sciences, which is based on adding the spectra of minerals in the relevant percentage, resulting in a final spectrum containing 100 per cent of the minerals.

The results of this work confirmed that there is a relationship between the modeled, altered and unaltered, basaltic surface and the measured spectrum from Martian instruments. Spectral deconvolution makes it possible to interpret the measured spectra from areas that are potentially difficult to explore or to choose interesting areas to explore on site. The method is described for mid-infrared because of software availability, but it can be successfully applied to shortwave spectra in near-infrared (NIR) band for data from the currently functioning Martian spectroscopes.

This work is the only one attempting modeling the spectra of the surface of Mars with a separated atmosphere and to determine the mineralogical composition.