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The purpose of this paper is to present an optimisation of four-point star-shaped structures produced through additive manufacturing (AM) polylactic acid (PLA). The study also aims to investigate the compression failure mechanism of the structure.

A Taguchi L₉ orthogonal array design of the experiment is adopted in which the input parameters are resolution (0.06, 0.15 and 0.30 mm), print speed (60, 70 and 80 mm/s) and bed temperature (55°C, 60°C, 65°C). The response parameters considered were printing time, material usage, compression yield strength, compression modulus and dimensional stability. Empirical observations during compression tests were used to evaluate the load–response mechanism of the structures.

The printing resolution is the most significant input parameter. Material length is not influenced by the printing speed and bed temperature. The compression stress–strain curve exhibits elastic, plateau and densification regions. All the samples exhibit negative Poisson’s ratio values within the elastic and plateau regions. At the beginning of densification, the Poisson’s ratios change to positive values. The metamaterial printed at a resolution of 0.3 mm, 80 mm/s and 60°C exhibits the best mechanical properties (yield strength and modulus of 2.02 and 58.87 MPa, respectively). The failure of the structure occurs through bending and torsion of the unit cells.

The optimisation study is significant for decision-making during the 3D printing and the empirical failure model shall complement the existing techniques for the mechanical analysis of the metamaterials.

To the best of the authors’ knowledge, for the first time, a new empirical model, based on the uniaxial load response and “static truss concept”, for failure mechanisms of the unit cell is presented.

While few studies have examined business-to-business (B2B) mobile application (app) usage, none have examined the challenges in developing these technological assets. This study aims to examine B2B marketing executives’ perceptions regarding benefits, barriers and facilitators in app development.

A survey of 311 B2B marketing executives at selling firms in the USA was conducted to identify key themes related to the benefits, barriers and facilitators in developing B2B apps. The research featured “open-ended” questions exclusively, and advanced textual and thematic analysis of executives’ responses produced several key themes.

Results show that the perceived benefit of lowering customer servicing and costs drives development more so than trying to realize new revenue opportunities (e.g. “saving” vs. “making” money). Achieving internal buy-in/participation was perceived as a larger barrier than the commitment of financial resources. Additionally, training and education were viewed as the strongest facilitators of an app’s success over its design and functionality. Implications for B2B firms are discussed.

The open-ended format of this research captures a greater breadth of perspectives at the expense of more granular analysis of any particular issue.

The themes generated from the responses offer novel insights into the benefits sought in developing an app, as well as the technological, organizational and environmental factors that act as barriers and facilitators. The open-ended format of this research captures a greater breadth of perspectives at the expense of a more granular analysis of any particular issue.

Within North American institutions of higher education, the sociopolitical construct of whiteness comprises an often implicit set of lessons that are reflected not only in policy and curricula but also in the teaching practices of faculty. Such lessons perpetuate white centricity and supremacy, at enormous costs to those who have been negatively racialized. Therefore, it is critical for white faculty to engage meaningfully with ongoing processes of self-reflection, self-education, and skill development so that they can contribute positively to the interrogation and disruption of whiteness in higher education. This chapter discusses seven processual considerations for white educators who seek to interrogate and disrupt the problem of whiteness in teaching and learning.

The objective of the study was to explore the factors influencing the career decisions of students doing the students' undergraduate (UG) and postgraduate (PG) programmes from urban private universities/colleges in the Indian context.

Career decision-making is determined by different factors and is contextual. The present study explores and identifies the prominent factors influencing career decision-making. A pool of 33 questions was developed, and these questions were initially administered to a sample of 233 students. Principal component analysis with Varimax Rotation identified salient factors. In the second study, confirmatory analysis was performed based on the opinion of 304 students.

The study shows that the student's career deciding factors include (1) career clarity, (2) career exploration, (3) career reward and recognition and (4) career initiative for professional and personal growth.

The study focussed on career-deciding factors for UG and PG students from urban universities/colleges in the Indian context and the findings can be used for planning career counselling interventions.

This study aims to focus on public policy concerning the implementation of public procurement policies in Nigeria and Ghana toward achieving value for money in the procurement of goods, services and works. It specifically analyzes some major administrative challenges Nigeria and Ghana are faced with in the administration/implementation of public procurement policies toward achieving value for money. It looks at the relationship between the state (regulatory authorities) and substate (procurement entities) in the public sectors of Nigeria and Ghana.

A comparative case study approach is adopted, where the two countries are compared in terms of achieving value for money. Data was collected from multiple sources, including in-depth interviews. The use of official documents and direct observations at the procurement regulatory authorities and entities’ premises.

This study found Nigeria often used the four Es – economy, efficiency, effectiveness and equity while Ghana mainly used the traditional five rights (right quantity, right quality, right price, right place and right time) as their criteria for ensuring value for money. The major administrative challenges found include corruption, low capacity of procurement personnel and poor knowledge of the procurement laws.

It recommends effective collaboration between government and civil society groups in the fight against corruption in procurement-related activities, with the implication that there is a need for periodic training for public procurement officials.

It adds to the field of public procurement in terms of value for money in the procurement of goods, services and works in developing countries context.

The COVID-19 pandemic has affected many industries, and reports indicate that this includes the illicit drug market. Recent research suggests that the homeless are particularly vulnerable during the pandemic, and the UK Government has acted to house rough sleepers. Research is scarce regarding homeless people’s experiences of the illicit drug market. This study aims to explore homeless people’s experiences of the drug supply in the UK during COVID-19.

Eight homeless people who use illicit drugs, residing in hostels for homeless people in Southampton, participated in semi-structured one-on-one telephone-based interviews.

A thematic analysis revealed five themes: availability of drugs, presence of dealers, quality of drugs, finances and personal experiences. Participants reported varying experiences of the drug supply, with lockdown measures expressed as the main reason for reduced supplies, as users found it difficult to find dealers and generate income for purchasing drugs.

The results may lack generalisability to the wider population, such as rough sleepers and drug dealers, suggesting a need for further research into people’s experiences of the drug supply during COVID-19. Research on this topic could be more in-depth through the use of research methods that are convenient for the homeless population.

Services should invest in harm reduction services and encourage homeless people who use drugs to engage in substitution treatment. Homeless services should provide psychological support for homeless people who use drugs.

The changes in homeless people’s behaviour following the pandemic may have implications for their interactions with the rest of society (e.g. begging in town centres may reduce). These changes in behaviour may also change the way society can best support homeless people.

The results are partially consistent with other research findings about the illicit drug supply; however, they also suggest that some individuals experienced minimal change in the illicit drug supply.

The purpose of this paper is to propose a new method that allows to compare the magnetic pressures of different pulse width modulation (PWM) strategies in a fast and efficient way.

The voltage harmonics are determined using the double Fourier integral. As for current harmonics and waveforms, a new generic model based on the Park transformation and a dq model of the machine was established taking saturation into consideration. The obtained analytical waveforms are then injected into a finite element software to compute magnetic pressures using nodal forces.

The overall proposed method allows to accelerate the calculations and the comparison of different PWM strategies and operating points as an analytical model is used to generate current waveforms.

While the analytical expressions of voltage harmonics are already provided in the literature for the space vector pulse width modulation, they had to be calculated for the discontinuous pulse width modulation. In this paper, the obtained expressions are provided. For current harmonics, different models based on a linear and a nonlinear model of the machine are presented in the referenced papers; however, these models are not generic and are limited to the second range of harmonics (two times the switching frequency). A new generic model is then established and used in this paper after being validated experimentally. And finally, the direct injection of analytical current waveforms in a finite element software to perform any magnetic computation is very efficient.