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Article
Publication date: 24 January 2020

Yuanhao Yu, Jingfu Song, Gai Zhao and Qingjun Ding

This paper aims to study the effect of different rare earth oxide on the tribological properties of polyimide (PI) nanocomposites based on the CNT and GO reinforcements.

Abstract

Purpose

This paper aims to study the effect of different rare earth oxide on the tribological properties of polyimide (PI) nanocomposites based on the CNT and GO reinforcements.

Design/methodology/approach

The PI nanocomposites filled with different rare earth oxide based on the carbon nanotubes and graphene oxide were designed and prepared by hot press sintering. The mechanical and tribological properties of PI nanocomposites were carried out, and their reinforcement mechanisms were discovered.

Findings

Rare earth oxide had a weak influence on the impact strength of PI nanocomposites. Filling La2O3 can dramatically reduce the friction coefficient and wear rate of PI nanocomposites.

Originality/value

The PI nanocomposites filled with rare earth oxide based on the CNT and GO reinforcements were designed, and their mechanical and tribological properties were studied.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 July 2011

L.Z. Liu, L. Weng, Y.X. Song, L. Gao, H. Zhao and Q.Q. Lei

The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)/Al…

Abstract

Purpose

The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)/Al2O3 nanocomposite films were prepared using different coupling agents.

Design/methodology/approach

Poly(amic acid) (PAA) was firstly synthesised from appropriate pyromellitic diannanocomposite and oxydianiline in N‐dimethylacetamide. Calculated amount of nano‐Al2O3 particles modified by different coupling agents (KH550, KH560, KH570 and AE3012) were added to PAA solution by an ultrasonic‐mechanical method and PI/nano‐Al2O3 film was fabricated by heat curing. The microstructure, thermal stability, mechanical properties and electric breakdown strength of the films were characterised.

Findings

The addition of coupling agents could greatly improve the dispersion homogeneity of Al2O3 nano‐particles in PI matrix. Results of corresponding characterisations indicated that both the thermal stability and mechanical properties of PI/Al2O3 nanocomposite film with KH550 were greater/better than others, while AE3012 could improve the electric breakdown strength.

Research limitations/implications

In the present discussion, the effects of different coupling agents, KH550, KH560, KH570 and AE3012, were investigated. Results of this research work would be beneficial to an in‐depth understanding on the relationship between microstructure and properties of PI composites, and further promote the development of the high‐performance PI insulating materials.

Originality/value

The four coupling agents, KH550, KH560, KH570 and AE3012, were firstly used to disperse the nano‐Al2O3 particles in PI matrix. The effects of coupling agents on microstructure and properties of composites were discussed by the authors in detail.

Article
Publication date: 3 November 2021

Peng Cai, Chengpeng Xu, Fei Zheng, Jingfu Song and Gai Zhao

The purpose of this paper is to investigate the effect of lanthana (La2O3) on the mechanical and tribological properties of polyimide (PI).

Abstract

Purpose

The purpose of this paper is to investigate the effect of lanthana (La2O3) on the mechanical and tribological properties of polyimide (PI).

Design/methodology/approach

The mechanical and tribological properties of PI nanocomposites filled with La2O3 were studied by molecular dynamic simulations to explore the deep mechanisms from an atomic or molecular view.

Findings

The results showed that the hardness of the PI matrix increased after La2O3 modification with a decrease of 72.4% nanoindentation depth. Besides, the friction coefficient of PI decreased by 72.2% after filling La2O3, and the shear deformation was largely reduced under the same conditions. The adsorption effect of La2O3 on the PI molecular, which reduced the atomic relative concentration, velocity, interaction with counterpart Fe layer and the temperature rise in the frictional interface, contributed to the improvement of the mechanical and tribological performance.

Originality/value

This study reveals the friction and wear mechanism of PI composites filled with rare earth oxide at the nanoscale.

Details

Industrial Lubrication and Tribology, vol. 73 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 March 2024

Melby Karina Zuniga Huertas, Thais Rubia Ferreira Lepre and André Torres Urdan

This paper aims to clarify the effect of discount discrepancy (DD) on consumers’ purchase intention (PI). The authors propose, test and provide evidence and explanations about the…

Abstract

Purpose

This paper aims to clarify the effect of discount discrepancy (DD) on consumers’ purchase intention (PI). The authors propose, test and provide evidence and explanations about the moderation of justification in the relation between consumers’ perceived DD and PI.

Design/methodology/approach

The authors conducted three experimental studies with a 2 × 2 factorial design, focusing on consumers’ processing of price discounts. Participants were informed that this study aimed to gather opinions on fashion, clothing and retail sales promotions. They accessed the questionnaire via Qualtrics. Each participant took part in only one study. The experimental conditions were manipulated through scenarios.

Findings

Study 1 tested and supported the moderation of justification on the effect of DD on PI. Study 2 tested and supported the moderation of the type of justification for the effect of DD on PI. Study 3 confirmed the findings in Study 2 and revealed the more effective type of justification.

Research limitations/implications

The authors focused on a typically hedonic product category (fashion clothing). Further research should include a wider variety of goods and services, which could lead to different explanations or generalizations.

Practical implications

Sales promotions must refrain from generating DD between the initial price discount and the subsequent smaller discounts. Practitioners must evaluate the gains of an initial, more considerable percentage discount to attract consumers to the store and sell them other products versus the cost of losing sales because of DD. Management should recognize the importance of giving the correct justification for perceived DD, aligning the firm’s justification with the consumer’s motivation to buy the product.

Social implications

The authors offer subsidies for effective consumer protection policies.

Originality/value

By studying the influence of justification on the effect of DD on PI, the authors propose a mechanism that would reduce the negative effect of DD on consumers’ PI.

Details

Management Research Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-8269

Keywords

Article
Publication date: 12 January 2024

Pengyun Zhao, Shoufeng Ji and Yuanyuan Ji

This paper aims to introduce a novel structure for the physical internet (PI)–enabled sustainable supplier selection and inventory management problem under uncertain environments.

Abstract

Purpose

This paper aims to introduce a novel structure for the physical internet (PI)–enabled sustainable supplier selection and inventory management problem under uncertain environments.

Design/methodology/approach

To address hybrid uncertainty both in the objective function and constraints, a novel interactive hybrid multi-objective optimization solution approach combining Me-based fuzzy possibilistic programming and interval programming approaches is tailored.

Findings

Various numerical experiments are introduced to validate the feasibility of the established model and the proposed solution method.

Originality/value

Due to its interconnectedness, the PI has the opportunity to support firms in addressing sustainability challenges and reducing initial impact. The sustainable supplier selection and inventory management have become critical operational challenges in PI-enabled supply chain problems. This is the first attempt on this issue, which uses the presented novel interactive possibilistic programming method.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 20 December 2023

Ormonde Cragun, Jason Kautz and Lin Xiu

This study aims to explore how individual-level and organizational-level factors interact to influence pay information (PI) seeking and PI sharing preferences in PI conversations…

Abstract

Purpose

This study aims to explore how individual-level and organizational-level factors interact to influence pay information (PI) seeking and PI sharing preferences in PI conversations (i.e. the face-to-face communications context). The authors examine how an individual’s judgment of their pay relative to others – or pay equity perception – affects their PI seeking and PI sharing preferences and how those relationships are affected by organizationally created pay transparency policies and pay transparency practices.

Design/methodology/approach

Using a 2 × 2 × 2 experimental design on the MTurk platform, the authors used a scenario-based prompt method to manipulate employee perceptions of pay equity and organizational pay transparency and tested those effects on employee pay disclosure preferences. The authors consider both pay policy and pay practice dimensions of pay transparency and both PI seeking and PI sharing dimensions of pay disclosure preferences. The final sample had 597 participants.

Findings

The authors find employees’ pay equity perceptions are negatively related to PI seeking behaviors and are even more so when organizations have restrictive pay transparency policies. Also, both pay transparency policy and pay transparency practice increase PI sharing preferences.

Originality/value

The authors provide insight into how individual perceptions drive pay disclosure motivations and the role of organizational policy and practice in influencing pay disclosure preferences within PI conversations. The authors provide insight into the antecedents that shape pay disclosure preferences, which lead to a both PI conversations among coworkers and an increase in one’s pay understanding. This study shows the contextual nature of PI seeking and PI sharing preferences, which are a motivational antecedent to pay-related sensemaking behaviors.

Abstract

Details

Functional Structure and Approximation in Econometrics
Type: Book
ISBN: 978-0-44450-861-4

Book part
Publication date: 1 October 2007

Mattias Ganslandt and Keith E. Maskus

The existence of parallel imports (PI) raises a number of interesting policy and strategic questions, which are the subject of this survey article. For example, parallel trade is…

Abstract

The existence of parallel imports (PI) raises a number of interesting policy and strategic questions, which are the subject of this survey article. For example, parallel trade is essentially arbitrage within policy-integrated markets of IPR-protected goods, which may have different prices across countries. Thus, we analyze fully two types of price differences that give rise to such arbitrage. First is simple retail-level trade in horizontal markets because consumer prices may differ. Second is the deeper, and more strategic, issue of vertical pricing within the common distribution organization of an original manufacturer selling its goods through wholesale distributors in different markets. This vertical price control problem presents the IPR-holding firm a menu of strategic choices regarding how to compete with PI. Another strategic question is how the existence of PI might affect incentives of IPR holders to invest in research and development (R&D). The global research-based pharmaceutical firms, for example, strongly oppose any relaxation of restrictions against PI of drugs into the United States, arguing that the potential reduction in profits would diminish their ability to innovate. There is a close linkage here with price controls for medicines, which are a key component of national health policies but can give rise to arbitrage through PI. We also discuss the complex economic relationships between PI and other forms of competition policy, or attempts to limit the abuse of market power offered by patents and copyrights. Finally, we review the emerging literature on how policies governing PI may affect international trade agreements.

Details

Intellectual Property, Growth and Trade
Type: Book
ISBN: 978-1-84950-539-0

Article
Publication date: 12 January 2024

Akmal Mirsadikov, Ali Vedadi and Kent Marett

With the widespread use of online communications, users are extremely vulnerable to a myriad of deception attempts. This study aims to extend the literature on deception in…

Abstract

Purpose

With the widespread use of online communications, users are extremely vulnerable to a myriad of deception attempts. This study aims to extend the literature on deception in computer-mediated communication by investigating whether the manner in which popularity information (PI) is presented and media richness affects users’ judgments.

Design/methodology/approach

This study developed a randomized, within and 2 × 3 between-subject experimental design. This study analyzed the main effects of PI and media richness on the imitation magnitude of veracity judges and the effect of the interaction between PI and media richness on the imitation magnitude of veracity judges.

Findings

The manner in which PI is presented to people affects their tendency to imitate others. Media richness also has a main effect; text-only messages resulted in greater imitation magnitude than those viewed in full audiovisual format. The findings showed an interaction effect between PI and media richness.

Originality/value

The findings of this study contribute to the information systems literature by introducing the notion of herd behavior to judgments of truthfulness and deception. Also, the medium over which PI was presented significantly impacted the magnitude of imitation tendency: PI delivered through text-only medium led to a greater extent of imitation than when delivered in full audiovisual format. This suggests that media richness alters the degree of imitating others’ decisions such that the leaner the medium, the greater the expected extent of imitation.

Details

Information & Computer Security, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2056-4961

Keywords

Article
Publication date: 20 December 2023

Indira Damarla, Venmathi M., Krishnakumar V. and Anbarasan P.

In this paper, a new front end converter (FEC) topology has been proposed for the switched reluctance (SR) motor drive. This study aims to present the performance analysis of…

Abstract

Purpose

In this paper, a new front end converter (FEC) topology has been proposed for the switched reluctance (SR) motor drive. This study aims to present the performance analysis of FEC-based SR motor drive using various types of control schemes like conventional proportional integral (PI) controller, fuzzy logic controller (FLC) and fuzzy-tuned proportional integral controller (Fuzzy-PI).

Design/methodology/approach

The proposed FEC-based SR motor drive with various control strategies is derived for the torque ripple minimization and speed control.

Findings

The steady state and the dynamic response of the FEC-based SR motor drive are analyzed using three different controllers under change in speed and loading conditions. The Fuzzy-PI-based control scheme improves the dynamic response of the system when compared with the FLC and the conventional PI controller.

Originality/value

The hardware prototype has been implemented for the FEC-based SR motor drive by using the Xilinx SPARTAN 6 FPGA processor. The experimental verification has been conducted and the results have been measured under steady state and dynamic conditions.

Details

Circuit World, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0305-6120

Keywords

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