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Article
Publication date: 13 December 2017

Ou Xie, Boquan Li and Qin Yan

This paper aims to develop a novel type of bionic underwater robot (BUR) with multi-flexible caudal fins. With the coordinate movement of multi-caudal fins, BUR will combine the…

Abstract

Purpose

This paper aims to develop a novel type of bionic underwater robot (BUR) with multi-flexible caudal fins. With the coordinate movement of multi-caudal fins, BUR will combine the undulation propulsion mode of carangiform fish and jet propulsion mode of jellyfish together organically. The use of Computational Fluid Dynamics (CFD) and experimental method helps to reveal the effect of caudal fin stiffness and motion parameters on its hydrodynamic forces.

Design/methodology/approach

First, the prototype of BUR was given by mimicking the shape and propulsion mechanism of both carangiform fish and jellyfish. Besides, the kinematics models in both undulation and jet propulsion modes were established. Then, the effects of caudal fin stiffness on its hydrodynamic forces were investigated based on the CFD method. Finally, an experimental set-up was developed to test and verify the effects of the caudal fin stiffness on its hydrodynamic forces under different caudal fin actuation frequency and amplitude.

Findings

The results of this paper demonstrate that BUR with multi-flexible caudal fins combines the hydrodynamic characteristics of undulation and jet propulsion modes. In addition, the caudal fin with medium stiffness can generate larger thrust force and reduce the reactive power.

Practical implications

This paper implies that robotic fish can be equipped with both undulation and jet propulsion modes to optimize the swimming performance in the future.

Originality/value

This paper provides a BUR with multi-propulsion modes, which has the merits of high propulsion efficiency, high acceleration performance and overcome the head shaken problem effectively.

Details

Industrial Robot: An International Journal, vol. 45 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 16 October 2018

Chuanxin Feng, Zewen Li and Haosheng Wang

This paper aims to investigate the effects of epoxy resin on the rheological and mechanical properties and water absorption rate of wood flour/high-density polyethylene (HDPE…

Abstract

Purpose

This paper aims to investigate the effects of epoxy resin on the rheological and mechanical properties and water absorption rate of wood flour/high-density polyethylene (HDPE) composites (wood-plastic composite [WPC]).

Design/methodology/approach

The reactive mixing of various epoxy resins with 60 Wt.% wood flour and HDPE was carried out in a twin-screw extruder with a special screw element arrangement. Polyethylene-grafted maleic anhydride (MAPE) was used as a coupling agent to improve the interfacial interaction between wood flour, epoxy resin and HDPE.

Findings

The tensile, flexural and impact properties of the composites increased initially and then decreased with the increasing content of epoxy resin. The complex viscosity decreased with increasing epoxy resin content, but a trend reversal was observed at 8 Wt.% epoxy resin. The epoxy resin-modified wood-HDPE composites chemically coupled by MAPE showed minimal water absorption.

Research limitations/implications

The cured epoxy resins impart high-aspect-ratio and plate-like polymeric fillers, affect the rheological behavior of the WPC and can also be oriented in a flow direction. Epoxy resin has good interaction with the cellulose structure of wood flour because of the polar functional groups within the cellulose.

Practical implications

This method provided a simple and practical solution to improve the performance of WPC.

Originality/value

The WPC modified by epoxy resin in this study had high performance in rheological and mechanical properties, and thus can be widely used for domestic, packaging and automotive applications.

Details

Pigment & Resin Technology, vol. 47 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 28 May 2024

Xiaohu Wen, Xiangkang Cao, Xiao-ze Ma, Zefan Zhang and Zehua Dong

The purpose of this paper was to prepare a ternary hierarchical rough particle to accelerate the anti-corrosive design for coastal concrete infrastructures.

Abstract

Purpose

The purpose of this paper was to prepare a ternary hierarchical rough particle to accelerate the anti-corrosive design for coastal concrete infrastructures.

Design/methodology/approach

A kind of micro-nano hydrophobic ternary microparticles was fabricated from SiO2/halloysite nanotubes (HNTs) and recycled concrete powders (RCPs), which was then mixed with sodium silicate and silane to form an inorganic slurry. The slurry was further sprayed on the concrete surface to construct a superhydrophobic coating (SHC). Transmission electron microscopy and energy-dispersive X-ray spectroscopy mappings demonstrate that the nano-sized SiO2 has been grafted on the sub-micron HNTs and then further adhered to the surface of micro-sized RCP, forming a kind of superhydrophobic particles (SiO2/HNTs@RCP) featured of abundant micro-nano hierarchical structures.

Findings

The SHC surface presents excellent superhydrophobicity with the water contact angle >156°. Electrochemical tests indicate that the corrosion rate of mild steel rebar in coated concrete reduces three-order magnitudes relative to the uncoated one in 3.5% NaCl solution. Water uptake and chloride ion (Cl-) diffusion tests show that the SHC exhibits high H2O and Cl- ions barrier properties thanks to the pore-sealing and water-repellence properties of SiO2/HNTs@RCP particles. Furthermore, the SHC possesses considerable mechanical durability and outstanding self-cleaning ability.

Originality/value

SHC inhibits water uptake, Cl- diffusion and rebar corrosion of concrete, which will promote the sustainable application of concrete waste in anti-corrosive concrete projects.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 22 October 2024

Ayham A.M. Jaaron, Mudaser Javaid and R.L. Fernando Garcia

This paper analyses the role of green human resources management (GHRM) practices on the application of logistics social responsibility (LSR) practices and examines the moderating…

Abstract

Purpose

This paper analyses the role of green human resources management (GHRM) practices on the application of logistics social responsibility (LSR) practices and examines the moderating effect of big data analytics (BDA) utilisation levels within these relationships.

Design/methodology/approach

Based on quantitative research methodology using survey data from 404 managers in the logistics service providers (LSPs) industry in the Philippines, PLS-SEM technique was used to test hypotheses formulated in this research.

Findings

Empirical results achieved suggest that GHRM practices have a significant positive impact on LSR. Among all individual GHRM practices, green training and development did not have any influence on LSR. While the results also revealed that BDA assimilation acts as a moderator of the relationship between GHRM and LSR, no support was found for the moderation effect of BDA acceptance or adoption on this relationship.

Originality/value

The study fills a gap in the logistics literature by introducing dynamic capabilities theory to the nexus between GHRM and SLR for the first time, which reveals previously unknown answers on effects of GHRM practices on LSR. The study also introduces BDA assimilation as an important moderator that can strengthen positive impact of GHRM on LSR.

Details

Management of Environmental Quality: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 1 April 2021

Md Delwar Hossain, Md Kamrul Hassan, Anthony Chun Yin Yuen, Yaping He, Swapan Saha and Waseem Hittini

The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour…

Abstract

Purpose

The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour (ignitibility, heat release rate and smoke toxicity) and various test method protocols. Additionally, the paper discusses the challenges and provides updated knowledge and recommendation on selective-fire mechanisms such as rapid-fire spread, air cavity and fire re-entry behaviours due to dripping and melting of lightweight composite claddings.

Design/methodology/approach

A comprehensive literature review on fire behaviour, fire hazard and testing methods of lightweight composite claddings has been conducted in this research. In summarising all possible fire hazards, particular attention is given to the potential impact of toxicity of lightweight cladding fires. In addition, various criteria for fire performance evaluation of lightweight composite claddings are also highlighted. These evaluations are generally categorised as small-, intermediate- and large-scale test methods.

Findings

The major challenges of lightweight claddings are rapid fire spread, smoke production and toxicity and inconsistency in fire testing.

Originality/value

The review highlights the current challenges in cladding fire, smoke toxicity, testing system and regulation to provide some research recommendations to address the identified challenges.

Details

Journal of Structural Fire Engineering, vol. 12 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Book part
Publication date: 16 September 2020

Ute Manecke

This chapter explores the challenges and opportunities that teaching and learning in a synchronous online environment pose by examining information literacy (IL) provision at the…

Abstract

This chapter explores the challenges and opportunities that teaching and learning in a synchronous online environment pose by examining information literacy (IL) provision at the Open University (OU), which will serve as a case study.

The OU provides distance education. While its flexibility offers more individuals an opportunity to start a course, it can be more challenging to ensure students develop their skills and knowledge and calls for innovative and engaging teaching methods.

The OU Library’s Live Engagement Team runs a program of digital information literacy (DIL) sessions. The team’s online pedagogy is built on retention and success and involves the careful planning, designing and delivering of DIL sessions, creating numerous interactive moments to increase teaching effectiveness.

The virtual enquiry desk allows students to consult library staff synchronously via the library helpdesk’s webchat service, which is delivered 24 hours a day. One of the advantages of this service is that students interact directly by having a dialogue with library staff in which they can ask further questions.

Both services carry out continuous reviews of the ways they operate, innovate and intervene. The chapter provides first-hand experiences of what has worked well in information literacy teaching in synchronous online spaces.

Abstract

Details

Review of Marketing Research
Type: Book
ISBN: 978-0-85724-726-1

Article
Publication date: 2 August 2019

Giridharan R., Raatan V.S. and Jenarthanan M.P.

The purpose of this paper is to study the effects of fiber length and content on properties of E-glass and bamboo fiber reinforced epoxy resin matrices. Experiments are carried…

Abstract

Purpose

The purpose of this paper is to study the effects of fiber length and content on properties of E-glass and bamboo fiber reinforced epoxy resin matrices. Experiments are carried out as per ASTM standards to find the mechanical properties. Further, fractured surface of the specimen is subjected to morphological study.

Design/methodology/approach

Composite samples were prepared according to ASTM standards and were subjected to tensile and flexural loads. The fractured surfaces of the specimens were examined directly under scanning electron microscope.

Findings

From the experiment, it was found that the main factors that influence the properties of composite are fiber length and content. The optimum fiber length and weight ratio are 15 mm and 16 percent, respectively, for bamboo fiber/epoxy composite. Hence, the prediction of optimum fiber length and content becomes important, so that composite can be prepared with best mechanical properties. The investigation revealed the suitability of bamboo fiber as an effective reinforcement in epoxy matrix.

Practical implications

As bamboo fibers are biodegradable, recyclable, light weight and so on, their applications are numerous. They are widely used in automotive components, aerospace parts, sporting goods and building industry. With this scenario, the obtained result of bamboo fiber reinforced composites is not ignorable and could be of potential use, since it leads to harnessing of available natural fibers and their composites rather than synthetic fibers.

Originality/value

This work enlists the effect of fiber length and fiber content on tensile and flexural properties of bamboo fiber/epoxy composite, which has not been attempted so far.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 5
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 September 2019

Kai Xie, Hao Xu and Jing Wu

The density and pattern of urban parks, traffic conditions are the main factors affecting urban park accessibility. To clarify the influence of traffic mode and urban road network…

Abstract

The density and pattern of urban parks, traffic conditions are the main factors affecting urban park accessibility. To clarify the influence of traffic mode and urban road network on urban park accessibility, we examine downtown area of Nanjing, China, and based on GIS network analysis, analyze urban park accessibility under different traffic modes in the current year (2017) and the Nanjing master planning target year (2030). The results shows: Using automobiles takes the shortest time to get to urban parks in 2017 and 2030 (if the problem of parking is ignored). Comparing the results of 2030 and 2017, by when the ground transportation network in the study area will be further improved, urban park accessibility was improved by a small margin under walking and automobile traffic modes, however, the density of rail traits increased fastest, urban park accessibility is improved most under this mode of transportation, rail transit route development becomes the dominant factor in improving park accessibility in downtown area of Nanjing. To a certain extent, this study reveals the leading factors of improving the accessibility of urban parks on the premise that the system of urban parks tends to be stable, and provides a reference for improving urban park accessibility.

Details

Open House International, vol. 44 no. 3
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 22 September 2023

Bhawesh Sah and Rohit Titiyal

Companies are adopting innovative methods for responsiveness and efficiency in the public transport sector. The implementation of air-taxi services (ATS) in the transport sector…

Abstract

Purpose

Companies are adopting innovative methods for responsiveness and efficiency in the public transport sector. The implementation of air-taxi services (ATS) in the transport sector is a move in this direction. Air taxis have a two-pronged advantage as they can reduce travel times by avoiding traffic congestion and have the potential to reduce carbon footprint compared to traditional modes of public transportation. Many companies worldwide are developing and testing ATS for practical applications. However, many factors may play a significant role in adopting ATS in the transport sector. This paper attempts to unearth such critical success factors (CSFs) and establish the interrelationships between these factors.

Design/methodology/approach

Fifteen CSFs were identified by systematically reviewing the literature and taking experts' input. An integrated multi-criteria decision-making (MCDM) technique, Decision-Making Trial and Evaluation Laboratory-Analytic Network Process (DEMATEL-ANP [DANP]) was used to envisage the causal relationships between the identified CSF.

Findings

The results reveal that Govt Regulations (GOR), Skilled Workforce (SKF) and Conductive Research Environment (CRE) are the most influential factors that impact the adoption of ATS in the transport sector.

Practical implications

The research implications of these findings will help practitioners and policymakers effectively implement ATS in the public transportation sector.

Originality/value

This is the first kind of study that identifies and explores the different CSFs for ATS implementation in public transportation. The CSFs are evaluated with the help of a framework built with inputs from logistics experts. The study recognizes the CSFs for ATS implementation and provides a foundation for future research and smooth adoption of ATS.

Details

International Journal of Productivity and Performance Management, vol. 73 no. 6
Type: Research Article
ISSN: 1741-0401

Keywords

1 – 10 of 476