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1 – 8 of 8Zhicai Yu, Lili Wang, Yiwei Shao, Yun Liu, Yuhang Zhao, Yi Qin, Yingzi Zhang and Hualing He
This study aims to fabricate a novel electromagnetic interference (EMI) shielding composite aerogel with both thermal insulation and high temperature warning functions.
Abstract
Purpose
This study aims to fabricate a novel electromagnetic interference (EMI) shielding composite aerogel with both thermal insulation and high temperature warning functions.
Design/methodology/approach
An emerging bio-based polypyrrole (PPy) gel/Fe3O4/calcium alginate (PFC) EMI shielding composite aerogel was prepared by freeze-drying and in situ polymerization method. First, Fe3O4/calcium alginate (CA) aerogel was obtained by freeze-drying the Fe3O4/CA mixture. Then, PPy/Fe3O4/CA was obtained by synthesizing PPy on the surface of CA/Fe3O4 aerogel through in situ polymerization. Finally, PPy/Fe3O4/CA was immersed in porphyrin solution (cross-linking agent) to get the final PFC EMI shielding composite aerogel.
Findings
Due to the matched impedance between Fe3O4 and PPy, the EMI shielding performance of PFC composite aerogel can reach up to −8 dB. In addition, the PFC EMI shielding composite aerogel also shows excellent self-extinguishing and thermal insulation properties. After leaving the flame, the burning PFC aerogel is quickly extinguished. When the PFC aerogel is placed on the heating plate at 230 °C, the temperature on the side of the aerogel away from the heating plate is only 90.3 °C after 5 min of heating. The electrical resistance of the PFC composite aerogel can be reduced from 3.62 × 104 O to 5 × 102 O to trigger the warning light after 3 s of exposure to the alcohol lamp flame. This reversible thermal resistance response characteristic can be used to give an early warning signal when the PFC encounters high temperature or flame.
Originality/value
This work provides a novel strategy for designing a multifunctional EMI shielding composite aerogel with repeatable high temperature warning performance. This PFC composite aerogel shows potential applications in the prevention of material combustion in high temperature electromagnetic environments.
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Fupeng Cheng, Jinglong Cui, Shuai Xu, Hongyu Wang, Pengchao Zhang and Juncai Sun
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange…
Abstract
Purpose
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange membrane fuel cells (PEMFCs), a protective Nb-modified layer is formed onto stainless steel via the plasma surface diffusion alloying method. The effect of diffusion alloying time on electrochemical behavior and surface conductivity is evaluated.
Design/methodology/approach
In this work, the surface electrical conductivity and corrosion resistance of modified specimen are evaluated by the potentiodynamic and potentionstatic polarization tests. Moreover, the hydrophobicity is also investigated by contact angle measurement.
Findings
The Nb-modified 430 SS treated by 1.5 h (1.5Nb) presented a lower passivation current density, lower interfacial contact resistance and a higher hydrophobicity than other modified specimens. Moreover, the 1.5 Nb specimen presents a smoother surface than other modified specimens after potentionstatic polarization tests.
Originality/value
The effect of diffusion alloying time on electrochemical behavior, surface conductivity and hydrophobicity of modified specimen is evaluated. The probable anti-corrosion mechanism of Nb-modified specimen in simulated acid PEMFC cathode environment is presented.
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Fupeng Cheng, Jinglong Cui, Shuai Xu, Song Li, Pengchao Zhang and Juncai Sun
The purpose of this study is to improve the performance of AISI 430 stainless steel (430 SS) in increasing its oxidation resistance, suppressing coating spalling and cracking…
Abstract
Purpose
The purpose of this study is to improve the performance of AISI 430 stainless steel (430 SS) in increasing its oxidation resistance, suppressing coating spalling and cracking, sustaining appropriate conductivity and blocking Cr evaporation as an interconnect material for intermediate temperature solid oxide fuel cells; a protective co-contained coating is formed onto stainless steel via the surface alloying process and followed by thermal oxidation.
Design/methodology/approach
In this work, oxidation behavior of coated specimen is studied during isothermal and cyclic oxidation measurements. Moreover, the conductivity is also investigated by area specific resistance (ASR) measurement.
Findings
Co-contained spinel layer shows an outstanding performance in preventing oxidation and improving conductivity compared with uncoated specimens. The protective spinel coating also reduces the ASR for coated specimen (0.0576O cm2) as compared to the uncoated specimen (1.87296O cm2) after isothermal oxidation.
Originality/value
The probable mechanism of co-contained alloy converting into spinel and the spinel transfer electron is presented.
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Sheau Fen (Crystal) Yap, Megan Phillips, Euejung Hwang and Yingzi Xu
Healthcare service is a process that comprises a series of touchpoints underlying the key facets of service delivery, collectively shaping the users' (i.e. patients, hospital…
Abstract
Purpose
Healthcare service is a process that comprises a series of touchpoints underlying the key facets of service delivery, collectively shaping the users' (i.e. patients, hospital staff, and visitors) experiences. Departing from most sensory studies dedicated to understanding the retail environment and hedonic service, this study focuses on how sensory knowledge can contribute to understanding the sensory-based experiences of hospital users and their interactions with healthcare services at multiple touchpoints.
Design/methodology/approach
This study employs a multi-method approach comprising two studies involving semi-structured interviews and a qualitative online survey of past patients.
Findings
Drawing upon the user-centered theory, the authors (1) consulted healthcare experts on hospital service touchpoints and standards around medical protocol; (2) explored users' needs, experiences, expectations, and evaluations of healthcare services; and (3) identified the issues and challenges faced by healthcare service users at various service touchpoints. Based on these insights, the authors proposed sensory tactics across healthcare service touchpoints that promote the well-being of major hospital users.
Research limitations/implications
The proposed sensory tactics require follow-up empirical evidence. Future research could adopt robust methodological designs on healthcare environmental interventions and progress with a transdisciplinary approach to advance this research area.
Practical implications
The authors' experience-based framework forms the basis of a valuable toolkit for healthcare service management.
Originality/value
This study advances services literature by integrating sense-based marketing knowledge with healthcare service research to understand the dynamic and interactive relationship between hospital users and the environment.
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Xu Yuhui, Liang Chengcheng and Wu Yue
To solve several “inorganic” problems generated recently by community development in China (e.g., waste of social resources, environmental pollution, and decreased economic energy…
Abstract
To solve several “inorganic” problems generated recently by community development in China (e.g., waste of social resources, environmental pollution, and decreased economic energy efficiency), focus should be on improving the community traffic organic micro-circulation system. As a historic and mixed functional urban community, the micro-circulation system of Xi'an Railway Bureau exhibits representativeness and complexity. Based on existing research results and years of follow-up investigations, which concentrate on circulation patterns and inherent organic development requirements of the community traffic micro-circulation system, this paper builds an evaluation index system. Value function method was used to implement the index factor quantitative analysis and comprehensive evaluation. Several related strategies were proposed to improve the organic micro-circulation system of the community, which is based on the analysis of the evaluation, in order to adopt the trend in both increasing urban development and stock updating. The analysis results demonstrate that it is necessary to present guiding renewal strategies on community land, road, people, and the environment for those mixed functional communities which use progressive renewed mode. It compensates the problems of overly strong export-oriented system, which is caused by the lack of organic traffic micro-circulation, so as to achieve the selective opening of community external. The study mainly highlights the significance of the systematic analysis of evaluation in influencing strategies on community renewal.
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The purpose of this guest editorial is to introduce the papers in this special issue.
Abstract
Purpose
The purpose of this guest editorial is to introduce the papers in this special issue.
Design/methodology/approach
A brief introduction about the issue of web‐mining applications in e‐commerce and e‐services is provided, along with a summary of the main contributions of the papers that are included in the special issue.
Findings
The value of web‐mining techniques can be enhanced through applying them to real environments such as e‐commerce and e‐services. The research fields of web mining, e‐commerce and e‐services can also be expanded.
Originality/value
An overview of the special issue and related research is provided in this paper.
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Lei Shen, Qing Liu, Zhebin Xue and Li Zhang
With the application and development of intelligent clothing and wearable technology, the term “micro-interaction” has gradually entered people’s lives. The paper aims to discuss…
Abstract
Purpose
With the application and development of intelligent clothing and wearable technology, the term “micro-interaction” has gradually entered people’s lives. The paper aims to discuss this issue.
Design/methodology/approach
The paper takes the concept of “micro-interaction” as the design principle, starting from the consumer demand, combing the realization mode of the intelligent safety clothing in recent years, and finds out the existing problems in the design of the intelligent safety clothing.
Findings
Under the concept of micro-interaction, a new theoretical model has been proposed to study intelligent safety clothing. Finally, the paper also emphasizes the importance of the industrialization of the proposed model.
Originality/value
The paper proposes a new research and development mode for intelligent clothing in safety protection area which is a pioneering study and can be valuable for safety clothing manufacturers to produce more functional and attractive products.
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Thomas Kundinger, Phani Krishna Yalavarthi, Andreas Riener, Philipp Wintersberger and Clemens Schartmüller
Drowsiness is a common cause of severe road accidents. Therefore, numerous drowsiness detection methods were developed and explored in recent years, especially concepts using…
Abstract
Purpose
Drowsiness is a common cause of severe road accidents. Therefore, numerous drowsiness detection methods were developed and explored in recent years, especially concepts using physiological measurements achieved promising results. Nevertheless, existing systems have some limitations that hinder their use in vehicles. To overcome these limitations, this paper aims to investigate the development of a low-cost, non-invasive drowsiness detection system, using physiological signals obtained from conventional wearable devices.
Design/methodology/approach
Two simulator studies, the first study in a low-level driving simulator (N = 10) to check feasibility and efficiency, and the second study in a high-fidelity driving simulator (N = 30) including two age groups, were conducted. An algorithm was developed to extract features from the heart rate signals and a data set was created by labelling these features according to the identified driver state in the simulator study. Using this data set, binary classifiers were trained and tested using various machine learning algorithms.
Findings
The trained classifiers reached a classification accuracy of 99.9%, which is similar to the results obtained by the studies which used intrusive electrodes to detect ECG. The results revealed that heart rate patterns are sensitive to the drivers’ age, i.e. models trained with data from one age group are not efficient in detecting drowsiness for another age group, suggesting to develop universal driver models with data from different age groups combined with individual driver models.
Originality/value
This work investigated the feasibility of driver drowsiness detection by solely using physiological data from wrist-worn wearable devices, such as smartwatches or fitness trackers that are readily available in the consumer market. It was found that such devices are reliable in drowsiness detection.
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