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Defence supply chains (SCs) aim at operational outcomes, and armed forces depend on them to provide availability and preparedness in peace and sustainability in war. Previous research has focussed on strategies for SCs aiming at financial outcomes. This raises the question of how suitable commercial supply chain strategies (SCSs) are for supply chain design (SCD) in defence. The purpose of this paper is to explain the constructs of SCSs that satisfy military operational requirements and to propose SCSs that are appropriate in defence.

This paper reports on a Delphi study with 20 experts from Swedish defence authorities. Through three Delphi rounds, two workshops and a validation round, these experts contributed to the reported findings.

The findings demonstrate that commercial SC constructs are acceptable and applicable in defence but not sufficient. An additional strategy is required to satisfy requirements on availability, preparedness and sustainability. The paper shows that different requirements in peace and war make it challenging to design suitable defence SCs and proposes eight SCSs that satisfy these requirements.

The results emanate from the Swedish defence context and further research is required for generalisation.

This paper extends theory by investigating SCs aiming at operational outcomes. For managers in companies and defence authorities, it explicates how the unique issues in defence must influence SCD to satisfy operational requirements.

Additive manufacturing (AM) methods such as material extrusion (ME) are becoming widely used by engineers, designers and hobbyists alike for a wide variety of applications. Successfully manufacturing objects using ME three-dimensional printers can often require numerous iterations to attain predictable performance because the exact mechanical behavior of parts fabricated via additive processes are difficult to predict. One of that factors that contributes to this difficulty is the wide variety of ME feed stock materials currently available in the marketplace. These build materials are often sold based on their base polymer material such as acrylonitrile butadiene styrene or polylactic acid (PLA), but are produced by numerous different commercial suppliers in a wide variety of colors using typically undisclosed additive feed stocks and base polymer formulations. This paper aims to present the results from an experimental study concerned with quantifying how these sources of polymer variability can affect the mechanical behavior of three-dimensional printed objects. Specifically, the set of experiments conducted in this study focused on following: several different colors of PLA filament from a single commercial supplier to explore the effect of color additives and three filaments of the same color but produced by three different suppliers to account for potential variations in polymer formulation.

A set of five common mechanical and material characterization tests were performed on 11 commercially available PLA filaments in an effort to gain insight into the variations in mechanical response that stem from variances in filament manufacturer, feed stock polymer, additives and processing. Three black PLA filaments were purchased from three different commercial suppliers to consider the variations introduced by use of different feed stock polymers and filament processing by different manufacturers. An additional eight PLA filaments in varying colors were purchased from one of the three suppliers to focus on how color additives lead to property variations. Some tests were performed on unprocessed filament samples, while others were performed on objects three-dimensional printed from the various filaments. This study looked specifically at four mechanical properties (Young’s modulus, storage modulus, yield strength and toughness) as a function of numerous material properties (e.g. additive loading, molecular weight, molecular weight dispersity, enthalpy of melting and crystallinity).

For the 11 filaments tested the following mean values and standard deviations were observed for the material properties considered: p_a = 1.3 ± 0.9% (percent additives), M_w = 98.6 ± 16.4 kDa (molecular weight), Ð = 1.33 ± 0.1 (molecular weight dispersity), H_m = 37.4 ± 7.2 J/g (enthalpy of melting) and = 19.6 ± 2.1% (crystallinity). The corresponding mean values and standard deviations for the resulting mechanical behaviors were: E = 2,790 ± 145 MPa (Young’s modulus), E’ = 1,050 ± 125 MPa (storage modulus), S_y = 49.6 ± 4.93 MPa (yield strength) and U_t = 1.87 ± 0.354 MJ/m^³ (toughness). These variations were observed in filaments that were all manufactured from the same base polymer (e.g. PLA) and are only different in terms of the additives used by the manufacturers to produce different colors or different three-dimensional printing performance. Unfortunately, while the observed variations were significant, no definitive strong correlations were found between these observed variations in the mechanical behavior of the filaments studied and the considered material properties.

These variations in mechanical behavior and material properties could not be ascribed to any specific factor, but rather show that the mechanical of three-dimensional printed parts are potentially affected by variations in base polymer properties, additive usage and filament processing choices in complex ways that can be difficult to predict.

These results emphasize the need to take processing and thereby even filament color, into account when using ME printers, they emphasize the need for designers to use AM with caution when the mechanical behavior of a printed part is critical and they highlight the need for continued research in this important area. While all filaments used were marked as PLA, the feedstock materials, additives and processing conditions created significant differences in the mechanical behavior of the printed objects evaluated, but these differences could not be accurately and reliably predicted as function of the observed material properties that were the focus of this study.

The testing methods used in the study can be used by engineers and creators alike to better analyze the material properties of their filament printed objects, to increase success in print and mechanical design. Furthermore, the results clearly show that as AM continues to evolve and grow as a manufacturing method, standardization of feedstock processing conditions and additives would enable more reliable and repeatable printed objects and would better assist designers in effectively implementing AM methods.

A deteriorating security situation and an increased need for defence equipment calls for new forms of collaboration between Armed Forces and the defence industry. This paper aims to investigate the ways in which the accelerating demand for increased security of supply of equipment and supplies to the Armed Forces requires adaptability in the procurement process that is governed by laws on public procurement (PP).

This paper is based on a review of current literature as well as empirical data obtained through interviews with representatives from the Swedish Defence Materiel Administration and the Swedish defence industry.

Collaboration with the globalized defence industry requires new approaches, where the PP rules make procurement of a safe supply of defence equipment difficult.

The study's empirical data and findings are based on the Swedish context. In order to draw more general conclusions in a defence context, the study should be expanded to cover more nations.

The findings will enable the defence industry and the procurement authorizations to better understand the requirements of Armed Forces, and how to cooperate under applicable legal and regulatory requirements.

The paper extends the extant body of academic knowledge of the security of supply into the defence sector. It serves as a first step towards articulating a call for new approaches to collaboration in defence supply chains.

The sustainable fashion (SF) literature is fragmented across the management discipline, leaving the path to a SF future unclear. As of yet, there has not been an attempt to bring these insights together or to more generally explore the question of “what is known about SF in the management literature and where could the SF field go from there?”. The purpose of this paper is to bring together the field to identify opportunities for societal impact and further research.

A systematic literature review was conducted from the first appearances of SF in the management literature in 2000 up to papers published in June 2019, which resulted in 465 included papers.

The results illustrate that SF research is largely defined by two approaches, namely, pragmatic change and radical change. The findings reveal seven research streams that span across the discipline to explore how organisational and consumer habits can be shaped for the future.

What is known about SF is constantly evolving, therefore, the paper aims to provide a representative sample of the state of SF in management literature to date.

This review provides decision makers with insights that have been synthesised from across the management field.

This review identifies knowledge gaps and informs managerial decision making in the field, particularly through serving as a foundation for further research.

The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.

The paper introduces and annotates periodical articles, monographs, and audiovisual material examining library instruction and information literacy.

The findings provide information about each source, discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.

The information may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.

The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.

The paper introduces and annotates periodical articles, monographs, and exhibition catalogues examining library instruction and information literacy.

The paper provides information about each source, discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.

The information may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.

The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.

The paper introduces and annotates periodical articles, monographs, and audiovisual material examining library instruction and information literacy.

Information is provided about each source, and the paper discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.

The information may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.

The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.

The paper introduces and annotates periodical articles, monographs, and audiovisual material examining library instruction and information literacy.

The paper provides information about each source, discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.

The information may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.

The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.

Introduces and annotates periodical articles, monographs, and audiovisual material examining library instruction and information literacy.

Provides information about each source, discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.

The information may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.