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Article
Publication date: 20 November 2020

S. Madhu and M. Balasubramanian

The purpose of this study is for solving many issues in production that includes processing of complex-shaped profile, machining of high-strength materials, good surface…

Abstract

Purpose

The purpose of this study is for solving many issues in production that includes processing of complex-shaped profile, machining of high-strength materials, good surface finish with high-level precision and minimization of waste. Among the various advanced machining processes, abrasive jet machining (AJM) is one of the non-traditional machining techniques used for various applications such as polishing, deburring and hole making. Hence, an overview of the investigations done on carbon fiber-reinforced polymer (CFRP) and glass fiber-reinforced polymer (GRFP) composites becomes important.

Design/methodology/approach

Discussion on various approaches to AJM, the effect of process parameters on the glass fiber and carbon fiber polymeric composites are presented. Kerf characteristics, surface roughness and various nozzle design were also discussed.

Findings

It was observed that abrasive jet pressure, stand-off distance, traverse rate, abrasive size, nozzle diameter, angle of attack are the significant process parameters which affect the machining time, material removal rate, top kerf, bottom kerf and kerf angle. When the particle size is maximum, the increased kinetic energy of the particle improves the penetration depth on the CFRP surface. As the abrasive jet pressure is increased, the cutting process is enabled without severe jet deflection which in turn minimizes the waviness pattern, resulting in a decrease of the surface roughness.

Research limitations/implications

The review is limited to glass fiber and carbon fiber polymeric composites.

Practical implications

In many applications, the use of composite has gained wide acceptance. Hence, machining of the composite need for the study also has gained wide acceptance.

Social implications

The usage of composites reduces the usage of very costly materials of high density. The cost of the material also comes down.

Originality/value

This paper is a comprehensive review of machining composite with abrasive jet. The paper covers in detail about machining of only GFRP and CFRP composites with various nozzle designs, unlike many studies which has focused widely on general AJM of various materials.

Details

World Journal of Engineering, vol. 18 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 18 April 2019

S. Rajendra Prasad, K. Ravindranath K. Ravindranath and M.L.S. Devakumar M.L.S. Devakumar

The choice of best machining parameters is an extremely basic factor in handling of any machined parts. The purpose of this paper is to exhibit a multi-objective…

Abstract

Purpose

The choice of best machining parameters is an extremely basic factor in handling of any machined parts. The purpose of this paper is to exhibit a multi-objective optimization technique; in view of weighted aggregate sum product assessment (WASPAS) technique toward upgrade the machining parameters in modified air abrasive jet machining (MAAJM) process: injecting pressure, stand-off distance (SOD), and abrasive mesh size measure with 100 rpm rotatable worktable on Nickel 233 alloy material. Three conflicting destinations, material removal rate (MRR), surface roughness (SR) and taper angles (Ta), respectively, are considered at the same time. The proposed procedure uses WASPAS, which is the examination of parametric optimization of the abrasive jet machining (AJM) process. The results was used any scopes of reactions in MAAJM process is the ideal setting of parameters are resolved through investigations represented. There is wide utilization of Nickel 233 in aviation enterprises; machining information on producing a hole utilizing MAAJM for the first time is given in this work, which will be helpful different industries.

Design/methodology/approach

This paper exhibits a multi-objective optimization technique; in view of WASPAS technique toward upgrade the machining parameters in MAAJM process: injecting pressure, SOD, and abrasive mesh size measure with 100 rpm rotatable worktable on Nickel 233 alloy material.

Findings

As an outcome of using the tool in any ranges of responses in the AJM process, the optimal setting of parameters is determined through experiments illustrated. The machining data of generating a hole using AJM are studied for the first time in this work, which will be useful for aerospace industries, where Nickel 233 is used broadly.

Originality/value

A new material in unconventional machining process and also a multi-objective optimization technique are adopted.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 3
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 8 July 2021

M. Balasubramanian and S. Madhu

The purpose of this study is to bring out the machining characteristics of abrasive jet machining on carbon fibre reinforced thermoplastic composites utilized in aerospace…

Abstract

Purpose

The purpose of this study is to bring out the machining characteristics of abrasive jet machining on carbon fibre reinforced thermoplastic composites utilized in aerospace and biomedical applications. Biocompatibility materials such as carbon fibres and polyether thermoplastics, like polyether ether ketone (PEEK) are widely used in trauma and orthopaedic surgery. Due to the heterogeneity, layered construction of reinforcing phase bonds with a resin matrix and abrasiveness of the reinforcing fibre, traditional drilling of carbon fibre-reinforced composites (CFRPs) are always challenging task.

Design/methodology/approach

An investigation is carried out using abrasive jet machine for drilling PEEK filled with 30 Wt.% carbon fibre (CF 30) using threaded and unthreaded nozzle to study the effect of abrasive jet process variables on surface roughness (Ra) and delamination factor (DF). Pressure (P) and stand-off distance (SOD) as important technological abrasive jet factors were evaluated. It is found that higher abrasive jet pressure and minimum SOD maybe selected to achieve minimum delamination.

Findings

The study further reported that the threaded nozzle minimized the surface roughness by 43% and delamination factor up to 12%.

Originality/value

This study of experimenting and observing the machining characteristics of CF30 by using a threaded nozzle is being tried for the first time and the results are deliberated.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Abstract

This essay aims at retracing the intellectual and biographical events of the economist Gino Arias (1879–1940), examining more in detail the two seasons at the opposite ends of his life: the early one that saw him considerably committed to the Zionist cause and the one that, thirty years later, would force him to confront the racial laws of the Fascist regime.

Despite the seeming tragic continuity of these two phases, Arias’s case is a real historiographical paradox since, over the long span between the opposite ends of his biography, not only did he distance himself from the Zionist movement, but he also gradually laid the foundations for his upcoming and immediate dedication to Fascism; indeed, within the Fascist regime he would stand out as an authoritative and influential theorist of corporatism, the institutional solution Mussolini tried to exploit to organize the national economic life.

After carefully examining Arias’s early contributions to the Zionist cause (that include the establishment of the Florentine Zionist Group and that led him toward strongly nationalistic stances), this essay sums up Arias’s intellectual biography during the next years and then, thanks to unprecedented documents from the Italian Ministry of Interior, closely looks into his fate after his conversion to Catholicism in 1932 and up against the racial laws of 1938, as well as into his attempts to escape persecution. A few final observations will then try to highlight the dramatic exemplarity of his case.

Details

A Research Annual
Type: Book
ISBN: 978-1-78441-154-1

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Article
Publication date: 8 June 2021

M. Balasubramanian and S. Madhu

The purpose of the study is to machine the composites at lower machining time with higher accuracy without causing delamination.

Abstract

Purpose

The purpose of the study is to machine the composites at lower machining time with higher accuracy without causing delamination.

Design/methodology/approach

Abrasive jet machining is the technology appropriate for machining composite materials to obtain good dimensional accuracy without causing de-lamination. The central composite design was followed in deciding the number of experiments to be carried out.

Findings

The influence of abrasive jet machining process parameters on machining time, material removal rate (MRR) and kerf characteristics were investigated. The experimental results proved the newly designed internal threaded nozzle increased MRR, thereby reducing the machining time.

Originality/value

Machining of glass fibre reinforced polymer (GFRP) is one of the challenging tasks given its non-linear and in-homogeneous properties. In this investigation, newly developed threaded and unthreaded nozzles in machining were used for making holes on the GFRP composites.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Case study
Publication date: 20 January 2017

Mark E. Parry and Janet Fitzgerald

Executives at this Internet-based company evaluate the results of a pricing survey to decide what changes to make, if any, to the annual fee charged for the company’s junk…

Abstract

Executives at this Internet-based company evaluate the results of a pricing survey to decide what changes to make, if any, to the annual fee charged for the company’s junk mail elimination services. Founded in 1996, Adios Junk Mail provides comprehensive elimination of unwanted direct-marketing solicitations. Clients select what types of direct marketing they want stopped. Once a month, the company generates a list of customers and their elimination preferences. It then mails the list to direct-mail companies, telemarketers, and database companies, requesting that the customers’ names be suppressed.

Details

Darden Business Publishing Cases, vol. no.
Type: Case Study
ISSN: 2474-7890
Published by: University of Virginia Darden School Foundation

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Article
Publication date: 8 February 2016

Ahmad Firdaus Shamsul Baharin, Mariyam Jameelah Ghazali and Juyana A Wahab

– The purpose of this paper is to make people aware of the increase usage of laser system in surface texturing process.

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Abstract

Purpose

The purpose of this paper is to make people aware of the increase usage of laser system in surface texturing process.

Design/methodology/approach

As it is a brief review paper, no particular method was used.

Findings

It has been found that most of the surface texturing methods used mas laser beam machining using Nd:YAG laser. It shows that the realization of the textured surface helps to reduce friction and wear which can increase the life span of a material.

Research limitations/implications

Most of the texturing is done on the substrates directly, and few research were conducted on coated surface of the material, which coating is also known as an excellent method to improve tribological properties.

Originality/value

The paper shows details on the recent development of surface texturing and its contribution to friction and wear reduction.

Details

Industrial Lubrication and Tribology, vol. 68 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 24 July 2019

Vasiliki Aitsidou, Anastasios Michailidis, Maria Partalidou and Olga Iakovidou

The purpose of this paper is to estimate respondents’ socio-ecological consciousness (SEC) (knowledge, perceptions, behaviour, habits and feelings) concerning household…

Abstract

Purpose

The purpose of this paper is to estimate respondents’ socio-ecological consciousness (SEC) (knowledge, perceptions, behaviour, habits and feelings) concerning household food waste (HFW) and to identify factors that influence attitude concerning HFW.

Design/methodology/approach

Data were collected through a questionnaire survey addressing to 279 residents in Western Macedonia, Greece. A principal component analysis was primarily applied to provide a manageable set of variables relevant to SEC. These variables were analyzed according to their positive/negative influence in SEC through descriptive statistics. Independent samples t-test analysis was employed to examine factors that influence HFW.

Findings

Results show that SEC is formed by three main activities: knowledge, perception and attitude. The survey reveals an inconsistency between existing knowledge and problematic perceptions, while the attitude includes neither harmful nor harmless HFW-related activities. A significant finding is that respondents’ age affects food rejection in different consumption stages in a household.

Research limitations/implications

Reliance on self-reported data for HFW that concerns a Greek case study does not allow a generalization of results.

Practical implications

The authors suggest a campaign plan for local bodies. The aim is to enhance respondents’ perceptual abilities and attitude concerning HFW. In order to raise awareness of students and individuals/households, related campaigns could be implemented by educational institutions and other policymakers.

Originality/value

The survey provides information for HFW, a topic not widely examined in Greece, and it is analyzed for the first time on the basis of SEC theory.

Details

British Food Journal, vol. 121 no. 9
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 3 October 2016

Iman Harymawan and John Nowland

The purpose of this study is to investigate how the earnings quality of politically connected firms is affected by changes in political stability and government…

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3272

Abstract

Purpose

The purpose of this study is to investigate how the earnings quality of politically connected firms is affected by changes in political stability and government effectiveness in a developing country.

Design/methodology/approach

This study uses a sample of 2,073 firm-year observations from 349 firms listed on the Indonesian Stock Exchange from 2003 to 2012 to examine how political stability and government effectiveness affect the earnings quality of politically connected firms, relative to non-politically connected firms. A two-stage model is used to address self-selection issues in the choice of firms to establish political connections.

Findings

This study finds that increased government effectiveness reduces the benefits of political connections, requiring politically connected firms to be more responsive to market pressures and resulting in higher earnings quality. However, increased political stability enhances the certainty of benefits from political connections, reducing the need for politically connected firms to respond to market pressures and resulting in lower earnings quality.

Research limitations/implications

For policymakers, these results indicate that different dimensions of political and economic development can affect the incentives of firms with political connections in different ways.

Originality/value

This study finds that the earnings quality of politically connected firms increases as government effectiveness improves, but it decreases as the political environment becomes more stable.

Details

International Journal of Accounting & Information Management, vol. 24 no. 4
Type: Research Article
ISSN: 1834-7649

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Article
Publication date: 15 November 2021

Chao-Chin Huang

With the increasing numbers of the elderly people, the aging segment represents a potential huge market. While this trend is obvious, still little literature focuses on…

Abstract

Purpose

With the increasing numbers of the elderly people, the aging segment represents a potential huge market. While this trend is obvious, still little literature focuses on this group. The study thus fills up this gap. Furthermore, the study aims to examine the aging consumers' journeys from the lens of brand resonance pyramid and has its importance using context-specific theories to understand the elderly consumers.

Design/methodology/approach

Case study method is conducted using the in-depth interview to collect data and inductive method via MaxQda software to analyze. Two types of aging brand (i.e. age-denial and age-adaptive) are investigated (Moody and Sood, 2010). This study interviews 26 elderly consumers, among whom, 12 have experiences in sports gyms (i.e. age-denial) and 14 in hospital services (i.e. age-adaptive). The author also triangulates the results by interviewing two additional experts in these contexts.

Findings

The findings of the paper reveal that (1) brand functional benefit is important for both age-denial and age-adaptive brands while each has different dimensions. Brand experiential benefit (e.g. social, behavioral and intellectual experience) is important motivation for the age-denial brand and brand symbolic and brand psychological benefits are the emotional drivers for the age-adaptive brand. (2) Consequences of this journey include those, for example, brand satisfaction, brand loyalty, word-of-mouth and recommendation and (3) mediating mechanisms, e.g. brand sense of identification, brand psychological attachment and customization for both brand types, with exceptions of diversification and brand psychological attachment, and mutual interaction for the age-denial brand and doctor–patient relationship and consumer inertia for the age-adaptive brand. (4) The current study finds two new concepts for aging consumers, i.e. brand social experience in the age-denial brand and brand psychological benefit in the age-adaptive brand.

Research limitations/implications

(1) Results of the paper are context dependent and generalization issue might occur. (2) While it is analyzed using inductive method via MaxQda software, the interviewer's subjective bias might occur. (3) Interviewees are at their different life stages, i.e. early-old vs mid-old, and thus, these contextual factors might also influence the results.

Originality/value

(1) The current study explores the elderly consumers' experience journeys at three stages (i.e. pre-service, during-service and pro-service/loyalty loop) for age-denial and age-adaptive brands and deepen an understanding of this aging market; (2) offers practical implications to brands targeting at the elderly consumers, particularly the age-denial and age-adaptive brands; (3) uses customer journey theory and brand resonance pyramid as the lens to understand aging consumers, and results also partly echo with the theories and (4) explores two new concepts for aging consumers, i.e. brand social experience and brand psychological benefit, thus adding new dimensions to important constructs, i.e. brand experience and brand benefit.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 34 no. 1
Type: Research Article
ISSN: 1355-5855

Keywords

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