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Article
Publication date: 3 August 2010

M. Brochu, D.W. Heard, J. Milligan and S. Cadney

The purpose of this paper is to outline the feasibility of using the electrospark welding (ESW) process to free‐form metallic components with nanostructured or amorphous…

541

Abstract

Purpose

The purpose of this paper is to outline the feasibility of using the electrospark welding (ESW) process to free‐form metallic components with nanostructured or amorphous microstructures.

Design/methodology/approach

ESW was used to deposit amorphous and nanostructure coatings for high‐wear resistance applications. The ESW process was also used to freeform three‐dimensional objects via multiple deposition passes. The near‐net shape capability is interesting as it significantly reduces the post‐processing operations.

Findings

This paper demonstrates that it is possible and economically feasible to produce components possessing metastable structures, i.e. nano or amorphous, using the ESW process.

Practical implications

The ESW process possesses the ability to manufacture advanced materials and can pattern surfaces to provide appropriate functionality with respect to the service environment.

Originality/value

This paper represents a summary of the capabilities of ESW to fabricate advanced materials and is based on the achievements of our laboratory. In particular, results on ESW of amorphous materials and the ability to produce coatings with second phase particles refined to this extent have not been achieved using other manufacturing methods.

Details

Assembly Automation, vol. 30 no. 3
Type: Research Article
ISSN: 0144-5154

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Publication date: 6 August 2024

Jeffrey A. Hayes

This chapter addresses one of the most common and long-standing problems among college students, namely depression, as well as a potential consequence of depression, suicide. A…

Abstract

This chapter addresses one of the most common and long-standing problems among college students, namely depression, as well as a potential consequence of depression, suicide. A formal definition of depression is presented, and symptoms of depression are discussed. Notably, clinical depression is differentiated from “feeling down” or having “the blues.” Common measures of depression for college students are described, and the current prevalence of depression among college students is explored, along with data pertaining to trends and trajectories. Particular attention is devoted to differences in rates and severity of depression among students of various ethnicities, gender identities, disabilities and sexual orientations. Next, the chapter covers various theories about and studies on the causes and consequences of depression, as well as preventive and remedial efforts that students can engage in to minimize the adverse effects of depression. The chapter concludes with a focus on college student suicide, including its prevalence, predictors of suicidal thoughts and behaviors and prevention and treatment of college student suicide.

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Article
Publication date: 17 September 2021

Sareh Götelid, Taoran Ma, Christophe Lyphout, Jesper Vang, Emil Stålnacke, Jonas Holmberg, Seyed Hosseini and Annika Strondl

This study aims to investigate additive manufacturing of nickel-based superalloy IN718 made by powder bed fusion processes: powder bed fusion laser beam (PBF-LB) and powder bed…

593

Abstract

Purpose

This study aims to investigate additive manufacturing of nickel-based superalloy IN718 made by powder bed fusion processes: powder bed fusion laser beam (PBF-LB) and powder bed fusion electron beam (PBF-EB).

Design/methodology/approach

This work has focused on the influence of building methods and post-fabrication processes on the final part properties, including microstructure, surface quality, residual stresses and mechanical properties.

Findings

PBF-LB produced a much smoother surface. Blasting and shot peening (SP) reduced the roughness even more but did not affect the PBF-EB surface finish as much. As-printed PBF-EB parts have low residual stresses in all directions, whereas it was much higher for PBF-LB. However, heat treatment removed the stresses and SP created compressive stresses for samples from both PBF processes. The standard Arcam process parameter for PBF-EB for IN718 is not fully optimized, which leads to porosity and inferior mechanical properties. However, impact toughness after hot isostatic pressing was surprisingly high.

Originality/value

The two processes gave different results and also responses to post-treatments, which could be of advantage or disadvantage for different applications. Suggestions for improving the properties of parts produced by each method are presented.

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Book part
Publication date: 6 September 2024

Courtney Dress

Body weight has a long history of functioning as a symbol of one’s beauty, social status, morality, discipline, and health. It has also been a standard inflicted much more…

Abstract

Body weight has a long history of functioning as a symbol of one’s beauty, social status, morality, discipline, and health. It has also been a standard inflicted much more intensely on women than men. While US culture has long idealized thinness for women, even at risky extremes, there is growing evidence that weight standards are broadening. Larger bodies are becoming more visible and accepted, while desire for and approval of a thin ideal has diminished. However, the continued widespread prevalence of anti-fat attitudes and stigma leaves uncertainty about just how much weight standards are changing. This study used an online survey (n = 320) to directly compare evaluations of thin, fat, and average size women through measures of negative stereotypes, prejudicial attitudes, and perceptions about quality of life. Results indicated that, as hypothesized, thin women were perceived less favorably than average weight women. However, fat women were perceived less favorably than both average and thin women. Men were harsher than women in their evaluations of only fat women. Additionally, participants being underweight or overweight did not produce an ingroup bias in their evaluations of underweight and overweight targets, respectively. That is, participants did not rate their own group more favorably, with the exception of overweight participants having lower prejudice toward overweight targets. These findings add to the emerging evidence that women’s weight standards are in transition, marked by an increasingly negative perception of thin women, though not necessarily growing positivity toward fat women. This evidence further points toward the need for more extensive research on attitudes of people across the entire weight spectrum.

Details

Embodiment and Representations of Beauty
Type: Book
ISBN: 978-1-83797-994-3

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Article
Publication date: 18 October 2024

Francisco Guzmán, Diego Alvarado-Karste, Fayez Ahmad, David Strutton and Eric L. Kennedy

Obesity imposes myriad negative consequences upon society, the economy and personal well-being. This study aims to investigate the effectiveness of using political correctness…

137

Abstract

Purpose

Obesity imposes myriad negative consequences upon society, the economy and personal well-being. This study aims to investigate the effectiveness of using political correctness (PC) in social marketing messages to persuade consumers to change their unhealthy behavior. It also explores various underlying mechanisms that drive this effect. Specifically, this research studies that messaging approach – politically correct vs politically incorrect and gain vs loss message framing – generates higher consumer intentions to change their behavior.

Design/methodology/approach

Four experiments were conducted with nationally representative samples to examine the effect of PC and gain vs loss message framing on consumers’ behavior changing intentions.

Findings

Politically correct prosocial marketing messages displayed higher persuasiveness than politically incorrect messages. Each relationship was mediated by the perceived manipulative capacity of the message and consumers’ attitudes toward the message. Message framing performed as a boundary condition for these effects.

Research limitations/implications

This paper sought to contribute to the literature that investigates the effectiveness of social marketing efforts. Three specific contributions related to the effects of message frames on politically correct and incorrect social marketing messages were developed.

Practical implications

The strategies presented in this paper benefit firms wishing to create a more prosocial approach to their business. A firm can present a prosocial message to their target market in a frame focusing on what will be gained instead of lost. Likewise, firms should welcome this type of messaging that embraces politically correct terminology instead of shying away from it.

Originality/value

This paper generates actionable insights for marketers and policymakers regarding how best to communicate with targeted segments about culturally- and personally sensitive topics related to obesity and weight loss. This paper also contributes to the literature that explores the effectiveness of social marketing initiatives. The findings suggest policymakers and social marketers should be cautious and, regardless of today’s sociopolitical environment, avoid falling into the temptation of developing politically incorrect and loss-framed messages.

Details

European Journal of Marketing, vol. 58 no. 11
Type: Research Article
ISSN: 0309-0566

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Article
Publication date: 8 May 2023

Berkay Ergene, Gökmen Atlıhan and Ahmet Murat Pinar

This study aims to reveal the influences of three-dimensional (3D) printing parameters such as layer heights (0.1 mm, 0.2 mm and 0.4 mm), infill rates (40, 70 and 100%) and…

265

Abstract

Purpose

This study aims to reveal the influences of three-dimensional (3D) printing parameters such as layer heights (0.1 mm, 0.2 mm and 0.4 mm), infill rates (40, 70 and 100%) and geometrical property as tapered angle (0, 0.25 and 0.50) on vibrational behavior of 3D-printed polyethylene terephthalate glycol (PET-G) tapered beams with fused filament fabrication (FFF) method.

Design/methodology/approach

In this performance, all test specimens were modeled in AutoCAD 2020 software and then 3D-printed by FFF. The effects of printing parameters on the natural frequencies of 3D-printed PET-G beams with different tapered angles were also analyzed experimentally, and numerically (finite element analysis) via Ansys APDL 16 program. In addition to vibrational properties, tensile strength, elasticity modulus, hardness, and surface roughness of the 3D-printed PET-G parts were examined.

Findings

It can be stated that average surface roughness values ranged between 1.63 and 6.91 µm. In addition, the highest and lowest hardness values were found as 68.6 and 58.4 Shore D. Tensile strength and elasticity modulus increased with the increase of infill rate and decrease of the layer height. In conclusion, natural frequency of the 3D-printed PET-G beams went up with higher infill rate values though no critical change was observed for layer height and a change in tapered angle fluctuated the natural frequency values significantly.

Research limitations/implications

The influence of printing parameters on the vibrational properties of 3D-printed PET-G beams with different tapered angles was carried out and the determination of these effects is quite important. On the other hand, with the addition of glass or carbon fiber reinforcements to the PET-G filaments, the material and vibrational properties of the parts can be examined in future works.

Practical implications

As a result of this study, it was shown that natural frequencies of the 3D-printed tapered beams from PET-G material can be predicted via finite element analysis after obtaining material data with the help of mechanical/physical tests. In addition, the outcome of this study can be used as a reference during the design of parts that are subjected to vibration such as turbine blades, drone arms, propellers, orthopedic implants, scaffolds and gears.

Social implications

It is believed that determination of the effect of the most used 3D printing parameters (layer height and infill rate) and geometrical property of tapered angle on natural frequencies of the 3D-printed parts will be very useful for researchers and engineers; especially when the importance of resonance is known well.

Originality/value

When the literature efforts are scanned in depth, it can be seen that there are many studies about mechanical or wear properties of the 3D-printed parts. However, this is the first study which focuses on the influences of the both 3D printing parameters and tapered angles on the vibrational behaviors of the tapered PET-G beams produced with material extrusion based FFF method. In addition, obtained experimental results were also supported with the performed finite element analysis.

Details

Multidiscipline Modeling in Materials and Structures, vol. 19 no. 4
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 23 August 2022

Germán Omar Barrionuevo, Jorge Andrés Ramos-Grez, Magdalena Walczak, Xavier Sánchez-Sánchez, Carolina Guerra, Alexis Debut and Edison Haro

The effect of processing parameters on the microstructure of steel produced by laser-based powder bed fusion (LPBF) is a recognized opportunity for property design through…

448

Abstract

Purpose

The effect of processing parameters on the microstructure of steel produced by laser-based powder bed fusion (LPBF) is a recognized opportunity for property design through microstructure control. Because the LPBF generates a textured microstructure associated with high anisotropy, it is of interest to determine the fabrication plane that would generate the desired property distribution within a component.

Design/methodology/approach

The microstructure of 316 L produced by LPBF was characterized experimentally (optical, scanning electron microscopy, glow discharge emission spectrometry and X-ray diffraction), and a finite element method was used to study the microstructure features of grain diameter, grain orientation and thermal parameters of cooling rate, thermal gradient and molten pool dimensions.

Findings

The computational tool of Ansys Additive was found efficient in reproducing the experimental effect of varying laser power, scanning speed and hatch spacing on the microstructure. In particular, the conditions for obtaining maximum densification and minimum fusion defects were consistent with the experiment, and the features of higher microhardness near the component’s surface and distribution of surface roughness were also reproduced.

Originality/value

To the best of the author’s knowledge, this paper is believed to be the first systematic attempt to use Ansys Additive to investigate the anisotropy of the 316 L SS produced by LPBF.

Details

Rapid Prototyping Journal, vol. 29 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 13 May 2014

Patricia V. Roehling, Mark V. Roehling, Ashli Brennan, Ashley R. Drew, Abbey J. Johnston, Regina G. Guerra, Ivy R. Keen, Camerra P. Lightbourn and Alexis H. Sears

The purpose of this paper is to use data from the 2008 and 2012 US Senate elections to examine the relationship between candidate size (obese, overweight, normal weight) and…

683

Abstract

Purpose

The purpose of this paper is to use data from the 2008 and 2012 US Senate elections to examine the relationship between candidate size (obese, overweight, normal weight) and candidate selection and election outcomes.

Design/methodology/approach

Using pictures captured from candidate web sites, participants rated the size of candidates in the primary and general US Senate elections. χ2 analyses, t-tests and hierarchical multiple regressions were used to test for evidence of bias against overweight and obese candidates and whether gender and election information moderate that relationship.

Findings

Obese candidates were largely absent from the pool of candidates in both the primary and general elections. Overweight women, but not overweight men, were also underrepresented. Supporting our hypothesis that there is bias against overweight candidates, heavier candidates tended to receive lower vote share than their thinner counterparts, and the larger the size difference between the candidates, the larger the vote share discrepancy. The paper did not find a moderating effect for gender or high-information high vs low-information elections on the relationship between candidate size and vote share.

Research limitations/implications

Further research is needed to understand the process by which obese candidates are culled from the candidate pool and the cognitions underlying the biases against overweight candidates.

Social implications

Because of the bias against obese political candidates, as much as one-third of the adult US population are likely to be excluded or being elected to a major political office.

Originality value

This study is the first to use election data to examine whether bias based on size extends to the electoral process.

Details

Equality, Diversity and Inclusion: An International Journal, vol. 33 no. 4
Type: Research Article
ISSN: 2040-7149

Keywords

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Article
Publication date: 1 July 2021

Radu Constantin Parpala, Diana Popescu and Cristina Pupaza

The mechanical performances of 3D-printed parts are influenced by the manufacturing variables. Many studies experimentally evaluate the impact of the process parameters on…

576

Abstract

Purpose

The mechanical performances of 3D-printed parts are influenced by the manufacturing variables. Many studies experimentally evaluate the impact of the process parameters on specimens’ static and dynamic behavior with the aim of tailoring the mechanical response of the prints. However, this experimental approach is hampered by the very large number of parameters, 3D printers and materials, the development of computer simulation models being thus required. In the context, this study aims to fill a gap by experimentally investigating the influence of infill related parameters over the vibrations of 3D-printed specimens, as well as to propose and validate a parametric finite element (FE) model for the prediction of eigenfrequencies.

Design/methodology/approach

A generally applicable FE model is not yet available for the 3D printing technology based on the material extrusion process due to the large number of parameters settings that determine a large variability of outcomes. Hence, the idea of developing numerical simulation models that address sets of parameters and assess their impact on a certain mechanical property. For the natural frequency, the influence of the infill density and infill line width is studied in this paper. An FE script that automates the generation of the model geometry by using the considered set of parameters is developed and run. The results of the modal analysis are compared to the experimental values for validating the script.

Findings

Based on the experimental results, a linear regression between the weight of the part and the first natural frequency is established. The response surfaces indicate that the infill density is the most significant parameter of influence. The weight-frequency function is then used for the prediction of the natural frequency of specimens manufactured with other infill parameters and values, including different infill patterns.

Practical implications

As the malfunctions or mechanical damages can be caused by the resonant vibration of parts during use, this research develops a FE-parameterized model that evaluates and predicts the eigenfrequencies of 2D printed parts to prevent these undesirable events. The targeted functional applications are those in which 3D-printed polymer parts are used, such as drone arms or drone propellers.

Originality/value

This research studies the influence of process parameters on the natural frequency of 3D-printed polylactic acid specimens, a topic scarcely addressed in literature. It also proposes a new approach for the development of parameterized FE models for sets of parameters, instead of a general model, to reduce the time and resources allocated to the experimental tests. Such a model is provided in this paper for evaluating the influence of infill parameters on 3D prints eigenfrequency. The numerical model is validated for other infill settings.

Details

Rapid Prototyping Journal, vol. 27 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 17 January 2020

X.R. Wang, Z.Q. Wang, T.S. Lin, P. He, R.J. Wang and M.Y. Bao

Electrospark deposition (ESD) attracts special attention from scientists and engineers because of its unique advantages. However, the ESD process has been carried out by hand up…

465

Abstract

Purpose

Electrospark deposition (ESD) attracts special attention from scientists and engineers because of its unique advantages. However, the ESD process has been carried out by hand up to the present. This prevents ESD from preparing complex curve/surface coatings owing to manual operation characteristics. To meet the coating precise preparation requirements for a lot of parts with complex surface from various industrial fields, this paper aims to obtain a new automatic ESD equipment, process and preparation methodology for complex surface coatings.

Design/methodology/approach

By designing a special deposition holder and re-programming programmable machine controller, an ESD power supply and a computer numerical control milling machine are integrated to obtain an electrospark-computer integrated deposition system (ES-CIDS). Then, based on the ES-CIDS, a new ESD process, named electrospark-computer numerical control deposition (ES-CNCD) is developed. Furthermore, complex surface coatings are depicted using non-uniform rational B-spline mathematical model and modeled in a special software developed via MATLAB. Finally, deposition programs for a complex coating are generated using golden section interpolation method, and transferred to and executed by the ES-CIDS to accomplish the preparation of the complex surface coating.

Findings

This paper demonstrates that it is possible and feasible to prepare complex surface coatings via an automatic ESD process (namely, ES-CNCD) precisely.

Research limitations/implications

This paper can make automatic ESD process get more attention from scientific researchers and engineers, and promote the research of the ES-CNCD process/equipment.

Practical implications

The ES-CNCD process can be used in the manufacturing of complex surface coatings, and in the remanufacturing of complex shape parts.

Social implications

The ES-CIDS/ES-CNCD can promote the development of related equipment and technology, and bring opportunities and employment to ESD industry.

Originality/value

This work prepares complex surface coatings precisely for the first time using a new automatic ESD process (ES-CNCD), which has wide application prospects in various industries.

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