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1 – 10 of over 115000Zhou Gaofeng, Zhao Yulong and Jiang Zhuangde
The flexibly thin film grid pressure sensor is mainly used to detect the interface pressure distribution between touching objects. Aim at larger measurement error, the strip…
Abstract
Purpose
The flexibly thin film grid pressure sensor is mainly used to detect the interface pressure distribution between touching objects. Aim at larger measurement error, the strip double sensing layer pressure sensor are designed and fabricated and tested.
Design/methodology/approach
Defects and characteristic of the flexibly thin film grid pressure sensor based on piezoresistive effect are analyzed and pointed out in this paper. After comparison of four sensors, the strip double sensing layer pressure sensor was thought to be best.
Findings
Experiment shows that the strip double sensing layer pressure sensor could eliminate the measurement error basically and illustrates the validity of measuring the interface pressure distribution between area touching objects.
Research limitations/implications
In this paper, only the strip double sensing layer pressure sensor was used to verify the validity of measuring the static interface pressure distribution between peach and platform. But there also exists some problems such as the adhering reliability of electrode and the unevenness of sensing layer. These problems could be overcome in the future research if the fabricating procedure and ingredient of material could be adjusted correctly.
Practical implications
The strip double sensing layer pressure sensor could be applied to detect the static interface pressure distribution such as peach pressure distribution. For dynamic measurement, this research needs to be done further.
Originality/value
Strip double sensing layer pressure sensor with simple “interlayer” structure and with low manufacture cost is presented to basically eliminate the measurement error of interface pressure distribution of original sensor.
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Marina Stramarkou, Achilleas Bardakas, Magdalini Krokida and Christos Tsamis
Carbon dioxide (CO2) has attracted special scientific interest over the last years mainly because of its relation to climate change and indoor air quality. Except for this, CO2…
Abstract
Purpose
Carbon dioxide (CO2) has attracted special scientific interest over the last years mainly because of its relation to climate change and indoor air quality. Except for this, CO2 can be used as an indicator of food freshness, patients’ clinical state and fire detection. Therefore, the accurate monitoring and controlling of CO2 levels are imperative. The development of highly sensitive, selective and reliable sensors that can efficiently distinguish CO2 in various conditions of temperature, humidity and other gases’ interference is the subject of intensive research with chemi-resistive zinc oxide (ZnO)-based sensors holding a privileged position. Several ZnO nanostructures have been used in sensing applications because of their versatile features. However, the deficient selectivity and long-term stability remain major concerns, especially when operating at room temperature. This study aims to encompass an extensive study of CO2 chemi-resistive sensors based on ZnO, introducing the most significant advances of recent years and the best strategies for enhancing ZnO sensing properties.
Design/methodology/approach
An overview of the different ZnO nanostructures used for CO2 sensing and their synthesis methods is presented, focusing on the parameters that highly affect the sensing mechanism and, thus, the performance of CO2 sensors.
Findings
The selectivity and sensitivity of ZnO sensors can be enhanced by adjusting various parameters during their synthesis and by doping or treating ZnO with suitable materials.
Originality/value
This paper summarises the advances in the rapidly evolving field of CO2 sensing by ZnO sensors and provides research directions for optimised sensors in the future.
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Syafiqah Ishak, Shazlina Johari, Muhammad Mahyiddin Ramli and Darminto Darminto
This review aims to give an overview about zinc oxide (ZnO) based gas sensors and the role of doping in enhancing the gas sensing properties. Gas sensors based on ZnO thin film…
Abstract
Purpose
This review aims to give an overview about zinc oxide (ZnO) based gas sensors and the role of doping in enhancing the gas sensing properties. Gas sensors based on ZnO thin film are preferred for sensing applications because of their modifiable surface morphology, very large surface-to-volume ratio and superior stability due to better crystallinity. The gas detection mechanism involves surface reaction, in which the adsorption of gas molecules on the ZnO thin film affects its conductivity and reduces its electrical properties. One way to enhance the gas sensing properties is by doping ZnO with other elements. A few of the common and previously used dopants include tin (Sn), nickel (Ni) and gallium (Ga).
Design/methodology/approach
In this brief review, previous works on doped-ZnO formaldehyde sensing devices are presented and discussed.
Findings
Most devices provided good sensing performance with low detection limits. The reported operating temperatures were within the range of 200̊C –400̊C. The performance of the gas sensors can be improved by modifying their nanostructures and/or adding dopants.
Originality/value
As of yet, a specific review on formaldehyde gas sensors based on ZnO metal semiconductors has not been done.
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Jiale Yang, Xianfeng Chen, Chuyuan Huang and Tianming Ma
With the acceleration of global energy structure transformation, hydrogen has been widely used for its non-pollution and high efficiency, and hydrogen detection is used to…
Abstract
Purpose
With the acceleration of global energy structure transformation, hydrogen has been widely used for its non-pollution and high efficiency, and hydrogen detection is used to guarantee the hydrogen safety. The purpose of this paper is to study the research foundation, trend and hotspots of hydrogen detection field.
Design/methodology/approach
A total of 4,076 literature records from 2000 to 2021 were retrieved from the core collection of the Web of Science database selected as data sources. The literature information mining was realized by using CiteSpace software. Bibliometrics was used to analyze information, such as keywords, authors, journals, institutions, countries and cited references, and to track research hotspots.
Findings
Since the 21st century, the number of publications in the hydrogen detection field has been in a stable stepped uptrend. In terms of research foundation, the hotspots such as core-shell structures, nano-hybrid materials and optical fiber hydrogen sensors have been studied extensively. In combination with the discipline structure and research frontier, the selectivity, sensitivity, response speed and other performance parameters of hydrogen sensors need further improvement. The establishment of an interdisciplinary knowledge system centered on materials science and electronic science will become a long-term trend in the research of hydrogen detection.
Originality/value
This study presents an overview of research status, hotspots and laws in hydrogen detection field, through the quantitative analysis of much literature in the field and the use of data mining, so as to provide credible references for the research of hydrogen detection technology.
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Presents the thoughts on decision processes of Chester I. Barnard, one of the century’s greatest management theorists. Includes his classic article, “Mind in everyday affairs”;…
Abstract
Presents the thoughts on decision processes of Chester I. Barnard, one of the century’s greatest management theorists. Includes his classic article, “Mind in everyday affairs”; his unpublished book, “The Significance of Decisive Behaviour in Social Action”; his correspondence with Herbert Simon, and significant comments found in his personal papers.
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Susan Samadi, Ghasem Asadi Cordshooli, Mohammad Yousefi, Khadijeh Kalateh and SeyedAmirabbas Zakaria
This paper aims to introduce constructed CeO2/TiO2 core/shell nanoparticle as sensitive substance organic compounds.
Abstract
Purpose
This paper aims to introduce constructed CeO2/TiO2 core/shell nanoparticle as sensitive substance organic compounds.
Design/methodology/approach
The CeO2 nanoparticles were synthesized by hydrothermal treatment. Then CeO2/TiO2 core/shell was fabricated by sol–gel method preparation of TiO2 in the presence of ceria nanoparticles and applied as the sensitive material to make a sensor.
Findings
Formation of the nanoparticles was confirmed by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The synthesized sensor exhibited not only good sensitivity to volatile organic compounds at room temperature but also logarithm of sensitivity versus concentrations was linear.
Research limitations/implications
The sensor shows acceptable sensitivity to volatile organic compound at room temperature.
Practical implications
Experimental data revealed satisfactory reproducibility and short response and recovery times.
Originality/value
A radical mechanism for gas sensor reaction in two pathways was considered and activation energies were calculated by density functional theory (DFT) method to describe different sensitivities of tested volatile gases. The experimental results were consistent with the calculations.
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A model for analysis of consumer behaviour towards food is developed. This model is intended to bridge the gap between the objective quality approach pursued in food sciences, the…
Abstract
A model for analysis of consumer behaviour towards food is developed. This model is intended to bridge the gap between the objective quality approach pursued in food sciences, the product characteristics approach, and the subjectively perceived quality approach, the product attribute approach as pursued in the consumer behaviour literature. The focus is on the information processing by the consumer. Information on the product quality is supplied to the consumer in the form of cues received while shopping or consuming. A distinction is made between extrinsic and intrinsic cues, and between search‐, experience‐, and credence‐quality attributes. Within the credence attributes, three categories are distinguished: food safety, health, and all other credence quality attributes. It is demonstrated that public policy should use minimum standards for regulating food safety, information and consumer education on health issues and definitional standards to regulate the other credence qualities. In the case of search quality, no public intervention is needed. In the case of experience quality, reputation is a means of reducing the quality erosion inherent for experience quality attributes. In the case of those foods which are not sold prepacked over the counter, these means are restricted. Here the public regulators could consider backing up the private quality policy efforts on labelling by implementing traceability schemes and defining the requirements for specific label claims.
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Maureen Alice Flynn and Niamh M. Brennan
The paper examines interviewee insights into accountability for clinical governance in high-consequence, life-and-death hospital settings. The analysis draws on the distinction…
Abstract
Purpose
The paper examines interviewee insights into accountability for clinical governance in high-consequence, life-and-death hospital settings. The analysis draws on the distinction between formal “imposed accountability” and front-line “felt accountability”. From these insights, the paper introduces an emergent concept, “grounded accountability”.
Design/methodology/approach
Interviews are conducted with 41 clinicians, managers and governors in two large academic hospitals. The authors ask interviewees to recall a critical clinical incident as a focus for elucidating their experiences of and observation on the practice of accountability.
Findings
Accountability emerges from the front-line, on-the-ground. Together, clinicians, managers and governors co-construct accountability. Less attention is paid to cost, blame, legal processes or personal reputation. Money and other accountability assumptions in business do not always apply in a hospital setting.
Originality/value
The authors propose the concept of co-constructed “grounded accountability” comprising interrelationships between the concept’s three constituent themes of front-line staff’s felt accountability, along with grounded engagement by managers/governors, supported by a culture of openness.
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The purpose of this paper is to compare the sensing characteristics of uniform fiber Bragg grating (FBG) and tilted fiber Bragg grating (TFBG) by presenting a detailed research…
Abstract
Purpose
The purpose of this paper is to compare the sensing characteristics of uniform fiber Bragg grating (FBG) and tilted fiber Bragg grating (TFBG) by presenting a detailed research review. Temperature, axial strain, bending, vibration and refractive index measurands of FBG and TFBG sensor are presented and some significant differences are found.
Design/methodology/approach
Theoretical analysis and practical application in engineering are investigated and compared from other authors' research papers and self analysis. Spectra behavior of both FBG and TFBG are discussed.
Findings
There are found to be significant differences in temperature, axial strain, bending, vibration and refractive index sensing characteristics of FBG and TFBG.
Originality/value
The paper's analysis is comprehensive and clear and provides readers with the sensing characteristics of FBG and TFBG in detail.
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Guangkai Sun, Yang Hu, Mingli Dong, Yanlin He, Mingxin Yu and Lianqing Zhu
Soft robotics is a burgeoning field owing to its high adaptability and safety in human–machine interaction and unstructured environments. However, the feedback control of soft…
Abstract
Purpose
Soft robotics is a burgeoning field owing to its high adaptability and safety in human–machine interaction and unstructured environments. However, the feedback control of soft actuators with flexible sensors is still a challenge.
Design/methodology/approach
To address this issue, this study proposes an optical fibre-based sensing membrane for the posture measurement of soft pneumatic bending actuators. The major contribution is the development of a flexible sensing membrane with a high sensitivity and repeatability for the feedback control of soft actuators. The characteristics of sensing membrane were analysed. The relationship between wavelength shift and bending curvature was derived. The curvatures of soft actuator were measured at four bending status, and the postures were reconstructed.
Findings
The results indicate that the measurement error is less than 2.1% of the actual bending curvature. The sensitivity is up to 212.8 pm/m−1, and the signal fluctuation in repeated measurements is negligible. This approach has broad application prospects in soft robotics, because it makes the optical fibre achieve more strength and compatible with soft actuators, thus improving the sensing accuracy, sensitivity and reliability of fibre sensors.
Originality/value
Different from previous approaches, an optical fibre with FBGs is embedded into a multilayered polyimide film to form a flexible sensing membrane, and the membrane is embedded into a soft pneumatic bending actuator as the smart strain limited layer which is able to measure the posture in real time. This approach makes the optical fibre stronger and compatible with the soft pneumatic bending actuator, and the sensing accuracy, sensitivity and reliability are improved. The proposed sensing configuration is effective for the feedback control of the soft pneumatic bending actuators.
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