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Article
Publication date: 6 July 2020

Johanna J. Schwartz, Joshua Hamel, Thomas Ekstrom, Leticia Ndagang and Andrew J. Boydston

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…

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Abstract

Purpose

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.

Design/methodology/approach

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).

Findings

For the 11 filaments tested the following mean values and standard deviations were observed for the material properties considered: pa = 1.3 ± 0.9% (percent additives), Mw = 98.6 ± 16.4 kDa (molecular weight), Ð = 1.33 ± 0.1 (molecular weight dispersity), Hm = 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), Sy = 49.6 ± 4.93 MPa (yield strength) and Ut = 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.

Research limitations/implications

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.

Practical implications

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.

Originality/value

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.

Details

Rapid Prototyping Journal, vol. 26 no. 7
Type: Research Article
ISSN: 1355-2546

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Book part
Publication date: 3 August 2020

Liam Fahey

Abstract

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The Insight Discipline: Crafting New Marketplace Understanding that Makes a Difference
Type: Book
ISBN: 978-1-83982-733-4

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Article
Publication date: 1 June 1997

Abbas J. Ali and Abdulrahman Al‐Aali

In 1987, the Harvard Business Review conducted a survey of its readers regarding the U.S. performance in the world markets. The study indicated that the U.S. had a deep‐seated…

117

Abstract

In 1987, the Harvard Business Review conducted a survey of its readers regarding the U.S. performance in the world markets. The study indicated that the U.S. had a deep‐seated problem of inadequate international competitiveness (Scott, 1987). More recently, Ernst & Young/American Quality Foundation undertook an International Quality Study which examined quality practices in Canada, Germany, Japan and the U.S. (See Bowles, 1992). The study revealed that 22 per cent of U.S. business always or almost always translate customer expectations into the design of new products and service. In Germany and Japan, the figure was 40 per cent and 58 per cent respectively. The results induced, Joshua Hammond, president of the American Quality Foundation, to state that “It is clear … that quality performance has a long way to go before it reaches parity with financial performance as a matter of primary importance to America's senior executives”. What makes the situation more complex and urgent is the fact that international competition has changed the structure of global markets and the rules of the business game. Furthermore, U.S. businesses no longer command the lead in the global marketplace and new international competitors are not only aggressive and competent, but appear to give priority to customer needs and expectations. For example, many Japanese companies view customer satisfaction as a way of building loyalty, thereby generating repeat sales. In contrast, U.S. executives have often aimed not at producing customer satisfaction, but at preventing customer dissatisfaction (Bowles, 1992). Similarly, the Fortune Global 500 List (Fortune 1995) showed that three countries accounted for the majority of the top 500 firms in the world; U.S. (151 firms), Japan (149 firms), and Germany (44 firms). Nevertheless, the list indicated that more Japanese companies have made it to the top ten (from three in 1993 to six in 1994), while the number of the U.S. firms stayed the same (three) in both years.

Details

Management Research News, vol. 20 no. 6
Type: Research Article
ISSN: 0140-9174

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Article
Publication date: 20 November 2017

Joshua Oluwasuji Dada

The purpose of this paper is to investigate the competence of Nigerian quantity surveyors with a view to identify and assess required areas of interest.

872

Abstract

Purpose

The purpose of this paper is to investigate the competence of Nigerian quantity surveyors with a view to identify and assess required areas of interest.

Design/methodology/approach

A structured questionnaire was administered among relevant groups of respondent (quantity surveyors, architects, engineers, builders and clients) in Nigeria. The respondents were asked to give rating, on a five-point Likert scale, on the required competencies (variables) expected of Nigerian quantity surveyors. A mean item score statistical analysis was used to rank the variables and compare them within the different groups. The analysis was undertaken using the Statistical Packages for Social Science tool. In exploring the underlying relationship among the competence requirement, factor analysis statistical technique was used to categorize them into key components.

Findings

The results of the study identified required competencies and factorized them into three components. These are as follows: procurement and value management; commercial management; and communication and entrepreneurship.

Originality/value

The findings provide insight into the competencies needed to be incorporated and/or intensified in the training of quantity surveyors in Nigeria.

Details

Engineering, Construction and Architectural Management, vol. 24 no. 6
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 11 February 2025

John Olatunji Adeoti, Olufemi Adebola Popoola and Joshua Adeyemi Afolabi

Nigeria’s quest to industrialize has received major attention in recent times. Special economic zones (SEZs) are thus recognized as capable of providing opportunities for firms to…

7

Abstract

Purpose

Nigeria’s quest to industrialize has received major attention in recent times. Special economic zones (SEZs) are thus recognized as capable of providing opportunities for firms to improve innovation capability and export performance. Limited empirical evidence exists on their economic impacts, particularly in terms of promoting innovation and exporting. This makes it difficult to provide accurate impact estimates or identify the channels through which the SEZ affects firm behavior. This study aims to specifically establish the Nigerian pattern of firm behavior in SEZs to improve the understanding of African SEZs and the appropriate incentives that can foster industrialization.

Design/methodology/approach

The study used primary data from a survey of firms in Nigeria’s active SEZs and in-depth interviews of major stakeholders. The primary data was collected through a semi-structured questionnaire administered to firms within the selected SEZs and an in-depth interview guide. The sampled SEZs were in Lagos, Ogun, Kano and Cross River States. In-depth interviews were conducted with the zone management, Nigerian Export Processing Zones Authority officials and the Manufacturers Association of Nigeria. Data were analyzed using descriptive statistics, content analyses of policy documents, principal component analysis, logit regression and two-stage least squares regression.

Findings

The results suggest that the number of incentives offered to SEZ firms does not matter for improved firm performance in terms of innovation and exports. Firms’ export performance is poor because firms do not comply with the basic tenet of SEZ as an area dedicated to free trade and consequent mandatory export of manufactures and services from the free trade enclave. Although firms in the Nigerian SEZs are considered to be fairly innovative, it is important to note that there is no evidence of innovation that is new to the world among these firms.

Research limitations/implications

The research team could not visit the zones in the Northeast region of the country due to insecurity. Some of the zones had also become inactive at the time of the survey, and the response rate from firms was very low. This limited the number of sampled firms.

Practical implications

The findings imply that the NEPZA Act needs to be revised to reflect the contextual realities of SEZs in Nigeria. The policies and details of each incentive offered by the government should be made clear to investors. For example, the permission given for SEZ firms to sell 100% of their manufactured, assembled or imported goods into the domestic market should be revisited as it obviously affects innovation and exports negatively. This would tremendously help SEZ firms fulfill their mandate of promoting exports, improving FDI attraction, enhancing industrialization and promoting economic competitiveness.

Originality/value

Previous studies have either focused on how SEZs affect innovation or influence export performance without accounting for the role of incentives in shaping innovation and export performance. This study fills this knowledge gap by providing evidence on the type of incentives for firms in Nigeria’s SEZs, investigating their effects (or otherwise) on innovation activities at the firm level and ascertaining how improvement in innovation capacity arising from the incentives affects firms’ export performance.

Details

International Journal of Innovation Science, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-2223

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Article
Publication date: 4 July 2016

Joshua Oluwasuji Dada and Nofiu Abiodun Musa

The purpose of this paper is to examine the factors affecting quantity surveyors’ competence with a view to reducing them to key components.

2285

Abstract

Purpose

The purpose of this paper is to examine the factors affecting quantity surveyors’ competence with a view to reducing them to key components.

Design/methodology/approach

The research adopts a data reduction system using the factor analysis statistical technique. A structured questionnaire was administered among major stakeholders in the Nigerian construction industry. The respondents were asked to give ratings on a 5-point Likert scale on factors affecting the competence of quantity surveyors. Based on the identified 11 factor variables, factor analysis was used to explore and detect the underlying relationship among the identified variables. Important measures such as Bartlett’s test of sphericity, Kaiser-Meyer-Olkin measure of sampling accuracy and measure of sampling adequacy were used to test the appropriateness of the factor extraction.

Findings

The data reduction results in three key factor components: organization structure and team development, industrial exposure and route of educational training.

Practical implications

The findings provide a considerable insight into the issue of factors affecting quantity surveyors’ competence and could have considerable implications on the training of quantity surveyors in Nigeria.

Originality/value

The paper provides information on major factors influencing the competence of quantity surveyors and the resulting implications on the training, development and practice of quantity surveying in Nigeria.

Details

Journal of Engineering, Design and Technology, vol. 14 no. 3
Type: Research Article
ISSN: 1726-0531

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Book part
Publication date: 17 September 2014

Naresh Kumar Agarwal

Through observing the use of iPhone and iPad by a child between the ages of two and four years and a half, this study presents accounts on the child’s use of and interaction with…

Abstract

Purpose

Through observing the use of iPhone and iPad by a child between the ages of two and four years and a half, this study presents accounts on the child’s use of and interaction with these devices, as well as her interaction with the physical environment.

Design/methodology/approach

Unstructured, naturalistic observation was employed in this study. The study is grounded in theories of user engagement with digital and physical objects.

Findings

A child’s interaction with touch-based devices does not deter the child from engaging effectively with the physical environment or from activities centered on creativity and interpersonal engagement. A child is able to move back and forth seamlessly between the physical and digital environments.

Practical implications

Findings from this study could help parents, educators, and system designers understand why and how toddlers and preschoolers use and engage with touch-based devices, as well as the kind of tasks they perform.

Originality/value

Studies of toddlers’ or preschoolers’ information behavior and interaction with touch-based devices are scarce. Children born toward the end of the first decade of the twenty-first century are growing up with a propensity to using touch-based devices. This study provides a framework for effective usage of such devices while ensuring all-round cognitive and physical development of the child.

Details

New Directions in Children’s and Adolescents’ Information Behavior Research
Type: Book
ISBN: 978-1-78350-814-3

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Article
Publication date: 1 October 2006

William C. Auden, Joshua D. Shackman and Marina H. Onken

The paper seeks to address four key Top Management Team (TMT) demographic characteristics in their relationship with firm performance: age, functional background, educational…

6767

Abstract

Purpose

The paper seeks to address four key Top Management Team (TMT) demographic characteristics in their relationship with firm performance: age, functional background, educational field, and team tenure. The study extends research on the TMT by explicitly introducing team performance as a new context measured in the form of International Risk Management Factor, in addition to demographic characteristic effects. International Risk Management Factor is developed based on multiple international risks trading off theory. In order to calculate that factor International Risk Management Index is introduced.

Design/methodology/approach

In the paper a sample of 212 firms was used, including 4,009 executives; also four hypotheses were tested. The hypotheses were tested using multiple regression analysis.

Findings

The findings in this paper support the proposition that top management team is an appropriate unit of study, due to its impact on firm performance. The results indicate that there is a significant correlation between TMT demographic characteristics and firm performance. This study concluded that three of the proposed four TMT demographic characteristics, including age, functional background, and team tenure influence firm performance. Results validate the proposition that TMT demographic characteristics show a significant positive correlation with firm performance, particularly when the accounting measure is applied. In addition, Top Management Team performance was positively correlated to team tenure, suggesting that as team tenure progresses team performance improves.

Originality/value

The paper differs in many features from previous research. Some of the most important aspects include scope of the study, scale of the sample, complexity of the moderated variable, uniqueness of moderated variable operationalization, and innovation in calculating International Risk Management Factor. For the first time, the study focuses exclusively on Top Management Team performance. The concept, which captures complexity of all TMT characteristics, is not included in demographic characteristics of TMT.

Details

Team Performance Management: An International Journal, vol. 12 no. 7/8
Type: Research Article
ISSN: 1352-7592

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Book part
Publication date: 17 August 2020

Joshua V. White and Vishal K. Gupta

Unlike other populations, entrepreneurs may be unable to fully escape from job-related stress due to their financial and/or psychological connection to their ventures. The authors…

Abstract

Unlike other populations, entrepreneurs may be unable to fully escape from job-related stress due to their financial and/or psychological connection to their ventures. The authors argue that stress is a universal, intangible variable that profoundly influences the entrepreneurial process. In the present review, the authors critically synthesize past literature to evaluate the substantive body of research on stress in entrepreneurship and assess the impact of stress on individuals’ well-being. The authors find that entrepreneurial stress stems from role conflict or overload, issues related to business operations, and concerns from life outside the venture. Further, stress may result in changes to personal satisfaction and psychological well-being, contingent upon an individual’s stress tolerance, coping strategies, or recovery practices. The entrepreneurial process, from creation to exit, is comprised of several transition periods, all of which are uniquely stressful. The authors explore the implications of our findings by discussing stressors that may manifest during each stage of the entrepreneurial process. Therefore, the authors respond to calls for more dynamic investigation of entrepreneurial stress while also highlighting the need for more research into stressors associated with specific entrepreneurial activities.

Details

Entrepreneurial and Small Business Stressors, Experienced Stress, and Well-Being
Type: Book
ISBN: 978-1-83982-397-8

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Article
Publication date: 1 May 1992

Robert J. Bruno

American businesses, like American politicians, often seek the quick fix that is best communicated by the short slogan. Quality is widely viewed as the American fix‐it‐all, with…

104

Abstract

American businesses, like American politicians, often seek the quick fix that is best communicated by the short slogan. Quality is widely viewed as the American fix‐it‐all, with the result that the word appears with great frequency in slogans, advertisements, and business visions.

Details

Journal of Business Strategy, vol. 13 no. 5
Type: Research Article
ISSN: 0275-6668

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