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Article
Publication date: 1 June 2004

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Sensor Review, vol. 24 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 1 April 1930

R.W. Sloley

AIRCRAFT INSTRUMENTS THE instruments used in aircraft are of a highly specialised nature. They have to stand up to very severe conditions in service. They are subjected to…

Abstract

AIRCRAFT INSTRUMENTS THE instruments used in aircraft are of a highly specialised nature. They have to stand up to very severe conditions in service. They are subjected to continual vibration during the whole time the engine is running, and to severe shocks in landing and when taxying on the ground. They are expected to function no matter what the position of the aircraft, and to stand reduced air pressures due to altitude, as well as a range of temperature altogether unusual in the case of instruments used for any other purpose. It is well to emphasise these peculiar conditions as they are not always fully appreciated.

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Aircraft Engineering and Aerospace Technology, vol. 2 no. 4
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 November 1961

W.G. Durbin

CONVENTIONAL aircraft thermometers are of the platinum‐resistance type, comprising one arm of a Wheatstone bridge network. The meter connected to the network is graduated…

Abstract

CONVENTIONAL aircraft thermometers are of the platinum‐resistance type, comprising one arm of a Wheatstone bridge network. The meter connected to the network is graduated on a temperature scale and different values are due to changes in the resistance of the platinum element. These arise from variations in the temperature of the air immediately in contact with the element or its protective casing. Any indicated temperature is a measure of the temperature of the air in contact with the thermometer. It is also the temperature of those parts of the aircraft over which the air is moving at the same speed as it is flowing past the thermometer. Since the air does not flow at the same speed over all parts of the aircraft it is clear that by mounting thermometers in different positions on an aircraft, different temperatures will be obtained. Due mainly to kinetic heating none of these will be the true temperature of the air in the free stream—i.e. away from the influence of the aircraft—and to obtain the free stream air temperature it is necessary to apply corrections. For many purposes, particularly meteorological research, it is important to be able to obtain true air temperatures from indicated air temperatures quickly and accurately and it is with this purpose in mind that the diagram to be described was devised and constructed.

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Aircraft Engineering and Aerospace Technology, vol. 33 no. 11
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 January 1996

L. Fradette, P.A. Tanguy, P. Hurez and D. Blouin

The design of vacuum calibrators for the cooling of complex PVC profilesis central to the production of high quality extrudates. One importantparameter governing cooling…

Abstract

The design of vacuum calibrators for the cooling of complex PVC profiles is central to the production of high quality extrudates. One important parameter governing cooling efficiency is the heat transfer coefficient at the interface between the stainless steel calibrator and the PVC extrudate, whose value is often taken as constant regardless of the extrusion velocity and the applied pressure vacuum. In this paper, a method is proposed to evaluate the variation of the heat transfer coefficient over the entire calibrator length. The idea is to use temperature measurements together with heat transfer simulation to derive a heat transfer correlation that can be used in practical design cases.

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International Journal of Numerical Methods for Heat & Fluid Flow, vol. 6 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 December 1999

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Industrial Lubrication and Tribology, vol. 51 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 17 March 2014

J. Virtanen, F. Yang, L. Ukkonen, A.Z. Elsherbeni, A.A. Babar and L. Sydänheimo

The purpose of this paper is to develop a novel totally passive, wireless temperature sensor tag based on ultra high-frequency (UHF) radio frequency identification (RFID…

Abstract

Purpose

The purpose of this paper is to develop a novel totally passive, wireless temperature sensor tag based on ultra high-frequency (UHF) radio frequency identification (RFID) technology. The temperature-sensing functionality is enabled by using distilled water embedded in the tag antenna substrate. The novel sensor tag is designed to provide wireless temperature readings comparable to a commercial thermocouple thermometer even in environments with high levels of interference, such as reflections. The structure of the novel sensor tag is aimed to increase its usability by minimizing user-created errors and to simplify the measurement procedure.

Design/methodology/approach

The sensor tag is based on a dual port sensing concept in which two ports are used to obtain sensor readings. By utilizing two ports instead of one, the effects of environmental interference, tag-reader antenna orientation and distance can be effectively minimized. Two alternative methods of acquiring the sensor reading from the operating characteristics of the two ports are presented and discussed.

Findings

Temperature measurements in practical scenarios show that by utilizing the dual port sensing concept, the developed tag produces temperature readings wirelessly which are comparable to readings from a commercial thermocouple thermometer.

Research limitations/implications

The concept of dual port sensing was shown and two alternative methods on extracting sensor readings from the differences in the port operating characteristics were introduced and discussed. In this paper, the dual port sensing concept is utilized in creating a temperature sensor tag; however, the same concept can be utilized in a variety of passive wireless sensors based on UHF RFID technology. This enables a new approach in designing accurate, easy to use and easily integrable passive sensors. The dual port sensing concept is in its early stages of development; its accuracy could be improved by developing more advanced data post-processing techniques.

Practical implications

The accuracy of a passive dual port UHF RFID-enabled temperature sensor tag is proven to be sufficient in many applications. This indicates that other sensor types utilizing the dual port sensing concept can reach high levels of accuracy as well. Furthermore, the passive RFID-enabled sensors based on the dual port sensing concept are superior in usability versus sensor tags equipped only with a single port. Therefore, dual port sensing concept in passive UHF RFID-enabled sensor tags could make such sensors more attractive commercially and lead to truly widespread ubiquitous sensing and computing.

Originality/value

This paper presents a novel passive, wireless temperature sensor tag for UHF RFID systems. The sensor tag utilizes a new structure which allows tight integration of two ports and two tag antennas. The accuracy of the developed tag is confirmed throughout measurements and it is found comparable to the accuracy of commercial thermometers in practical measurement scenarios. Moreover, the paper presents a dual port sensing concept and two readout methods based on the concept which are aimed to increase the accuracy and usability of all kinds of UHF RFID-enabled sensor tags.

Details

Sensor Review, vol. 34 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 18 September 2007

Wenjun Liu and Bozhi Yang

The goal of this review paper is to provide information on several commonly used thermography techniques in semiconductor and micro‐device industry and research today.

Abstract

Purpose

The goal of this review paper is to provide information on several commonly used thermography techniques in semiconductor and micro‐device industry and research today.

Design/methodology/approach

The temperature imaging or mapping techniques include thin coating methods such as liquid crystal thermography and fluorescence microthermography, contact mechanical methods such as scanning thermal microscopy, and optical techniques such as infrared microscopy and thermoreflectance. Their principles, characteristics and applications are discussed.

Findings

Thermal issues play an important part in optimizing the performance and reliability of high‐frequency and high‐packing density electronic circuits. To improve the performance and reliability of microelectronic devices and also to validate thermal models, accurate knowledge of local temperatures and thermal properties is required.

Originality/value

The paper provides readers, especially technical engineers in industry, a general knowledge of several commonly used thermography techniques in the semiconductor and micro‐device industries.

Details

Sensor Review, vol. 27 no. 4
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 1 March 1930

J.F. Alcock

IN research or development work on aero engines there are many occasions when it is desirable, or sometimes essential, to obtain temperature readings under somewhat…

Abstract

IN research or development work on aero engines there are many occasions when it is desirable, or sometimes essential, to obtain temperature readings under somewhat difficult conditions. In many cases it is possible for serious errors to arise, under conditions which make their detection difficult, and the writer, therefore, thinks that the information he has gained in dealing with these problems may be of value to others.

Details

Aircraft Engineering and Aerospace Technology, vol. 2 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 February 1991

C. Lea

The three European Community manufacturers of commercially available wetting balances for measuring the solderability of electronic components have participated in an…

Abstract

The three European Community manufacturers of commercially available wetting balances for measuring the solderability of electronic components have participated in an intercomparison assessment of surfaces of standard solderability that have the potential for calibrating the balance instruments. The development of the standard surfaces, as well as the small adjustments needed to improve the uniformity of design of the different instruments, and the standardisation of the procedures for their use, have been described in the preceding papers in this series. This paper gives details of the experimental procedures used for the intercomparison and the significance of the comparative data from each balance type.

Details

Soldering & Surface Mount Technology, vol. 3 no. 2
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 1 June 1941

F.G. Spreadbury

GENERALLY speaking, the demand for thermo‐electric pyrometer equipment is such that individual calibration of each instrument and its couple is possible. For the…

Abstract

GENERALLY speaking, the demand for thermo‐electric pyrometer equipment is such that individual calibration of each instrument and its couple is possible. For the measurement of aircraft temperatures thermo‐electric pyrometers are employed but the following conditions render individual calibration impracticable:

Details

Aircraft Engineering and Aerospace Technology, vol. 13 no. 6
Type: Research Article
ISSN: 0002-2667

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