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This paper seeks to present the results of an experiment to investigate the effect of six part orientation (XY, XZ, YX, YZ, ZY, ZX) and a wide range of energy densities on ultimate tensile strength (UTS) and elongation of laser‐sintered nylon 12 (PA‐12) test specimens.

ASTM Type 1 specimens were built on a DTM Sinterstation 2500+ and tensile tested on an Instron 5569 A. The resulting data were fit to non‐linear regression models based on the well‐known Weibull growth model to predict each response based on the total energy density used in each trial.

The resulting regression models provide excellent fits with low sum of squared errors and normally distributed residuals. The resulting material properties are highly affected by the energy density and the build orientation. However, once sufficient energy density is applied, properties tend to converge to consistent values. To achieve maximum UTS of approximately 52 MPa, it is recommended that values of energy density above 0.25 W‐s per mm³ be used. To achieve maximum elongation of approximately 15‐16 percent, it is recommended that values of energy density above 0.40 W‐s per mm³ be used when building parts in the XY, XZ, YX, YZ orientations. Parts built in the ZX orientation exhibit lower elongation values at or below 12 percent for even high values of energy density.

This paper extends previous work of Starr, Gornet and Usher on the relationship between material properties, part orientation and energy density by proposing the use of the Weibull growth model. Recommendations are provided to assist users in the selection of correct energy density to achieve desirable mechanical properties in each specified orientation.

This paper aims to present a systematic approach for building information modelling (BIM) implementation for architectural SMEs at the organizational level

The research is undertaken through a knowledge transfer partnership (KTP) project between the University of Salford and John McCall Architects (JMA) a SME based in Liverpool. The overall aim of the KTP is to develop lean design practice through BIM adoption. The BIM implementation approach uses a socio‐technical view, which does not only consider the implementation of technology but also considers the socio‐cultural environment that provides the context for its implementation. The action research oriented qualitative and quantitative research is used for discovery, comparison, and experimentation as it provides “learning by doing”.

The strategic approach to BIM adoption incorporated people, process and technology equally and led to capacity building through the improvements in process, technological infrastructure and upskilling of JMA staff to attain efficiency gains and competitive advantages.

The paper introduces a systematic approach for BIM adoption based on the action research philosophy and demonstrates a roadmap for BIM adoption at the operational level for SME companies.

This paper describes the results of an effort to predict future freight volume in the truckload (TL) trucking industry. The approach involves the use of stepwise multiple linear regression models that relate freight volume to a variety of economic indicators. The models are built using a large set of actual freight data provided by J.B. Hunt Transport (JBHT), one of the world’s largest TL carriers. The data was first analyzed using the overall set of national data, and then for specific industrial and regional segments. The overall results of these analyses should prove useful to a wide variety of transportation and logistics operations.

The purpose of this paper is to examine whether or not driver life, carrier performance, and customer service can be improved as a result of the use of a technique called yard‐stacking in the truckload trucking industry. The technique seeks to find ways to provide level freight availability during normal weekly cycles in an effort to seek improvement relative to all constituencies.

Simulation is used to examine the use of yard‐stacking on Fridays to provide additional freight on weekends, which is generally much less available than on weekdays. In this technique, before being dispatched on Friday for a long‐haul, a driver initially picks up a load to make a short “dray” move from the customer site to the carrier's closest terminal yard. During the weekend, another driver picks up the drayed load. In this research, we evaluate the potential of weekend yard‐stacking under a variety of scenarios.

The paper shows that a carrier's adaptation of weekend freight leveling can be beneficial to both trucking companies and their customers, while remaining relatively neutral to drivers.

Carriers may be able to utilize Friday yard‐stacking to improve their cost efficiency, driver satisfaction and customer performance.

This research extends the knowledge base of truckload freight imbalance problems. It was industrially motivated by J.B. Hunt Transport, Inc., one of the world's largest truckload carriers, who provided freight data and conceptual guidance.

This paper seeks to develop and present a new mathematical formulation to determine the optimal preventive maintenance and replacement schedule of a system.

The paper divides the maintenance‐planning horizon into discrete and equally‐sized intervals and in each period decide on one of three possible actions: maintain the system, replace the system, or do nothing. Each decision carries a specific cost and affects the failure pattern of the system. The paper models the cases of minimizing total cost subject to a constraint on system reliability, and maximizing the system reliability subject to a budgetary constraint on total cost. The paper presents a new mathematical function to model an improvement factor based on the ratio of maintenance and repair costs, and show how it outperforms fixed improvement factor models by analyzing the effectiveness in terms of cost and reliability of the system.

Optimal decisions in each period over a planning horizon are sought such that the objectives and the requirements of the system can be achieved.

The developed mathematical models for this improvement factor can be used in theoretical and practical situations.

The presented models are effective decision tools that find the optimal solution of the preventive maintenance and replacement scheduling problem.

The purpose of this paper is to measure the effect of process conditions on mechanical properties of laser‐sintered nylon 12 (Duraform^®) and to determine the range of conditions that provide consistent mechanical performance for additive manufacturing.

Tensile test specimens were fabricated over a range of well‐characterized process conditions including laser power, laser speed, scan spacing, layer thickness, build orientation, and build position. Tensile modulus, yield strength, ultimate tensile strength and elongation‐at‐fracture were measured and related to process parameters.

Tensile properties are strongly related to the amount of energy deposited during scanning. Strength and modulus approach their maximum values as the energy deposited exceeds the amount needed to fully melt the applied powder. Elongation‐at‐fracture does not reach its maximum until higher energy‐melt ratio. Performance of blends with reused powder matches that of virgin powder when blend composition is adjusted to a standard melt‐flow index. The volumetric energy density and the energy‐melt ratio are useful for correlating mechanical properties with multiple process parameters and material thermal properties.

This work presents the most extensive data to date on mechanical properties of nylon 12 (Duraform^®) as they relate to the full range of process parameters. These data show that mechanical performance correlates strongly with the volume energy density. In contrast to the area energy density (a.k.a. Andrews Number), this volumetric parameter includes the effect of varying layer thickness and can be related directly to the melting characteristics of the polymer material. Within the parameter range studied, this relationship allows adjustment of one scan parameter for improved speed or dimensional accuracy while ensuring good strength by an offsetting adjustment of another parameter. Such trade‐offs will be important in future manufacturing applications of the laser sintering process. Understanding the energy‐melt ratio provides insight into the relationship between scan conditions and the physics of powder melting and sintering, and offers a methodology to relate results at other bed temperatures and with other polymer powders.

This study aims to offer a bibliometric analysis of the already substantial and growing literature on global virtual teams (GVTs).

Using a systematic literature review approach, it identifies all articles in the Web of Science from 1999 to 2021 that include the term GVTs (in the title, the abstract or keywords) and finds 175 articles. The VOSviewer software was applied to analyze the bibliometric data.

The analysis revealed three dialogizing research clusters in the GVTs literature: a pioneering management information systems and organizational cluster, a general management cluster and a growing international management and behavioural studies cluster. Furthermore, it highlights the most cited articles, authors, journals and nations, and the network of strong and weak links regarding co-authorships and co-citations. Additionally, this study shows a change in research patterns regarding topics, journals and disciplinary approaches from 1999 to 2021. Finally, the analysis illustrates the position and centrality in the network of the most relevant actors.

The findings can guide management practitioners, educators and researchers to the most meaningful clusters of publications on GVTs, and help navigate and make sense of the vast body of the available literature. The importance of GVTs has been growing in the past two decades, and Covid-19 has accelerated the trend.

This study provides an updated and comprehensive systematic literature review on GVTs. To the best of the authors’ knowledge, it is also the first systematic literature review and bibliometry on GVTs. It concludes by suggesting future research paths.

The debate about corporate purpose is a recurring one that has re-emerged today. What should be the guiding principles of business: the pursuit of profit or a contribution to public interest? We trace key elements in this debate in Britain and America, from the interwar years, when John Maynard Keynes and Adolf Berle made important contributions, to the 1970s, when events ushered in a return to laissez-faire and the rise to dominance of the shareholder primacy model of corporate governance and purpose, to today. Both the earlier and the current debates are centered around whether we see business institutions as strictly private entities, transacting with their suppliers, workers, and customers on terms agreed with or imposed upon these groups, or as part of society at large and therefore expected to contribute to what society deems to be its interests. Whether current developments will ultimately produce a shift in corporate purpose akin to the one that followed the Second World War remains to be seen. But the parallels to the interwar debates, and the uncertain economic, political, and social environments in which they took place, are striking. Our objective is to see what might be learned from the past to inform the current direction of thought concerning capitalism and corporate purpose.