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This paper reviews the range of sensors used in electronic nose (e‐nose) systems to date. It outlines the operating principles and fabrication methods of each sensor type as well as the applications in which the different sensors have been utilised. It also outlines the advantages and disadvantages of each sensor for application in a cost‐effective low‐power handheld e‐nose system.

The paper aims to provide a technical review of the application of quantum dot (QD) technology to sensors.

Following a brief introduction to QD technology, this paper considers recent research on QD‐based physical, chemical and gas sensors.

This shows that QDs are being exploited in a range of experimental sensors for detecting physical variables, notably radiant/electromagnetic quantities and temperature; chemical compounds, such as metals and many species of clinical interest; and a variety of gases and vapours. Prospects also exist to develop improved sources and detectors for use in optical gas sensors.

The paper does not consider biomedical uses of QDs such as cellular imaging, bioassays and biosensors.

This provides a detailed insight into recent research on physical, chemical and gas sensors based on QD technology.

Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.

This paper is aimed at Engineers involved in production wire‐bonding processes and system maintenance. It traces the development of microbonding from its origins to the present day. Principles and techniques are examined and some approaches to fault diagnosis are explored.

Electro‐Science Laboratories have recently introduced two new mixed‐bonded ternary conductors that form excellent cermet resistor terminations. Made of platinum, palladium, and silver (Pt/Pd/Ag), ESL 9565 and 9566 are more oxidation‐resistant during overglaze firing (500–525°C) than more commonly used palladium/silver (Pd/Ag) metallisations. Therefore they solder wet more easily after overglazing than with Pd/Ag.

This paper describes a new method designed for a quartz tuning‐fork temperature sensor. This sensor is designed with a new cut ZYtw(115°/15°) and it is shown that this worked best in flexural vibration mode. The way for raising signal to noise ratio and reducing equivalent resistor of the sensor were analyzed in theory. A manufacturing method has been determined to form and adjust the precise frequency, which could improve sensitivity and reduce non‐linearity.

High-altitude ice crystals (HAICs) are causing one in-flight event or more per month for commercial aircraft. The effects include preventing air data probes (pitot pressure and total air temperature in particular) from functioning correctly and causing engines to roll back and shut down. The purpose of this study is to describe the process used by the National Research Council Canada (NRC) to develop and test a particle detection probe (PDP). The probe mounts on the fuselage of aircraft to sense and quantify the ice crystals in the environment.

The probe was demonstrated on the NRC Convair and Airbus A340 research aircraft as part of the European Union HAIC programme. The probe was ruggedised, adapted for easy installation in standard aircraft fittings and tested in a variety of conditions for longevity and endurance.

Efforts to achieve the safety requirements for flight on aircraft are discussed. The challenges, surprises and opportunities for testing on which the development group is capitalised are also presented.

It was demonstrated that the detectors gave signals proportional to the ice crystal content of clouds, and results demonstrating the functionality of the probe are presented.

This paper describes the multi-year process of developing the NRC PDP from a test cell sensor for detecting engine exhaust contaminants on an aircraft ice crystal detection probe. The work included over 20 flight tests on NRC aircraft and the Airbus HAIC test programme.

The purpose of this study is to clarify the mechanism of ambient and transient temperature effects on piezoelectric pressure sensors, and to propose corresponding compensation measures. The temperature of the explosion field has a significant influence on the piezoelectric sensor used to measure the shock wave pressure. For accurate shock wave pressure measurement, based on the actual piezoelectric pressure sensors used in the explosion field, the effects of ambient and transient temperatures on the sensor should be studied.

The compensation method of the ambient temperature is discussed according to the sensor size and material. The theoretical analysis method of the transient temperature is proposed. For the transient temperature conduction problem of the sensor, the finite element simulation method of structure-temperature coupling is used to solve the temperature distribution of the sensor and the change in the contact force on the quartz crystal surface under the step and triangle temperatures. The simulation results are highly consistent with the theory.

Based on the analysis results, a transient temperature control method is proposed, in which 0.5 mm thick lubricating silicone grease is applied to the sensor diaphragm, and 0.2 mm thick fiberglass cloth is wrapped around the sensor side. Simulation experiments are carried out to verify the feasibility of the control method, and the results show that the control method effectively suppresses the output of the thermal parasitic.

The above thermal protection methods can effectively improve the measurement accuracy of shock wave pressure and provide technical support for the evaluation of the power of explosion damage.

There are various temperature measuring systems presented in the literature and on the market today. Over the past number of years a range of luminescent‐based optical fibre sensors have been reported and developed which include fluorescence and optical scattering. These temperature sensors incorporate materials that emit wavelength shifted light when excited by an optical source. The majority of commercially available systems are based on fluorescent properties.Design/methodology/approach – Many published journal articles and conference papers were investigated and existing temperature sensors in the market were examined.Findings – In optical thermometry, the light is used to carry temperature information. In many cases optical fibres are used to transmit and receive this light. Optical fibres are immune to electromagnetic interference and are small in size, which allows them to make very localized measurements. A temperature sensitive material forms a sensor and the subsequent optical data are transmitted via optical fibres to electronic detection systems. Two keys areas were investigated namely fluorescence based temperature sensors and temperature sensors involving optical scattering.Originality/value – An overview of optical fibre temperature sensors based on luminescence is presented. This review provides a summary of optical temperature sensors, old and new which exist in today's world of sensing.

The purpose of this paper is to discuss results of laboratory tests performed on a point type Faraday magnetic field scanner device designed for monitoring applications.

Automated laboratory setup using a reference magnetic induction source was used to test key parameters such as spatial resolution and signal to noise ratio.

Volume scans of magnitude of the magnetic field induction vector prove applicability of the sensor and demonstrate its advantages.

Sensor is applicable for safe and accurate scanning of the magnetic induction spatial distribution.

The paper presents a novel test setup.