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Article
Publication date: 1 June 2004

C.A. Wilson, R.M. Laing and T. Tamura

The aim of this work was to validate the Wilson and Laing theoretical mathematical model for estimating the intrinsic “dry” thermal resistance of upper‐bedding, and compare the…

Abstract

The aim of this work was to validate the Wilson and Laing theoretical mathematical model for estimating the intrinsic “dry” thermal resistance of upper‐bedding, and compare the two‐dimensional models commonly used to estimate the “dry” thermal resistance of bedding in use, with the actual intrinsic “dry” thermal resistance measured using an infant thermal manikin. The Wilson and Laing model was the only model used adequately to estimate the intrinsic “dry” thermal used resistance of materials arranged over the infant thermal manikin. Estimation of intrinsic “dry” thermal resistance of bedding during use is not adequate using two‐dimensional models. Further investigation into the relationship between thermal resistance, conditions of use, and SIDS using the Wilson and Laing model is recommended.

Details

International Journal of Clothing Science and Technology, vol. 16 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 15 August 2016

Sridhar N. Ramaswami, Sekar Raju and Dana C. Page

This research aims to examine two constructs that define loyal brand relationships – greater resistance to changing their brand beliefs and attitudes (resistance to change) and…

Abstract

Purpose

This research aims to examine two constructs that define loyal brand relationships – greater resistance to changing their brand beliefs and attitudes (resistance to change) and greater willingness to shun competitor brands (determinism). The paper develops and tests psychometrically sound scales to measure these two constructs and proposes and tests a model that identifies antecedent and outcome linkages between resistance and determinism and other brand relationship measures across two studies.

Design/methodology/approach

Scale development was done following the guidelines recommended by Nunnally and Bernstein (1994) and Churchill (1979). Factor analysis was used to test scale item fit. Discriminant validity, scale reliability tests, nomological and predictive validity tests were conducted.

Findings

This study adds to the literature by identifying the specific dimensions that compose the resistance concept. It finds that strong resistance leads to determinism at the high end. It also finds that brand engagement is an outcome of resistance. In addition, three sub-components of the resistance dimension – resistance to new products that offer higher value, resistance to value improvements of competing offerings and resistance to quality deterioration for the focal or object brand – are also identified and scale items developed to measure them.

Research limitations/implications

Resistance to change and determinism are less understood and researched concepts in the context of brand relationships. Further, these two dimensions are of particular importance in emerging markets such as India because of the changes taking place in these markets with the introduction of many global brands competing with traditional strong brands. For new brands, a key question is how to reduce the resistance that consumers exhibit toward trying out new brands. For existing brands, the key question is how to leverage the resistance that consumers have in trying out a new brand so that greater determinism is built and defections are minimized. This research helps answer some of these questions.

Originality/value

The primary purpose of the study was to identify the specific dimensions that compose the resistance concept. An important aspect of brand relationships is the ability to foster greater strength in the relationship. While the important of resistance has been known, a good scale to measure it has been lacking.

Details

Journal of Indian Business Research, vol. 8 no. 3
Type: Research Article
ISSN: 1755-4195

Keywords

Article
Publication date: 1 March 1990

L. De Schepper, W. De Ceuninck, H. Stulens, L.M. Stals, R. Vanden Berghe and S. Demolder

A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method…

Abstract

A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.

Details

Microelectronics International, vol. 7 no. 3
Type: Research Article
ISSN: 1356-5362

Article
Publication date: 1 February 1995

B.N. Ellis

Surface insulation, electrochemical migration and various other insulation resistances are terms which are often glibly used, sometimes even incorrectly. This paper categorises…

Abstract

Surface insulation, electrochemical migration and various other insulation resistances are terms which are often glibly used, sometimes even incorrectly. This paper categorises different types of insulation resistance and catalogues about twenty practical applications of insulation resistance measurement, each with its ideal general conditions of measurement (test voltage, bias voltage, bias polarity, test voltage period, test frequency, test duration, temperature, humidity, test pattern type, test pattern dimensions, voltage gradients, tolerances, etc.) This description is independent of any of the nearly forty known, often contradictory, standards, most of which no longer correspond to the practical printed circuit or assembly of today. Also discussed are the different technologies of insulation resistance measurement, starting with the original non‐electronic ‘Megger®’ types through to modern laboratory electrometers and, finally, instrumentation specific to the practical measurement of printed circuit insulation resistances, including static and dynamic types. The importance of automatic statistical analyses is emphasised, especially with production testing as well as qualification procedures. This paper is aimed not only at those wishing to learn what modern insulation resistance testing is all about, but also at experienced persons wanting to marshall their thoughts about the fundamental meanings of insulation testing for different applications and specifications.

Details

Circuit World, vol. 21 no. 2
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 December 2002

Michele L. Crossley

Recent empirical and theoretical research suggests increasing resistance by the general public to health promotion messages and interventions. Using the recently developed “health…

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Abstract

Recent empirical and theoretical research suggests increasing resistance by the general public to health promotion messages and interventions. Using the recently developed “health resistance scale” this paper presents the comparative results obtained in a number of different samples. The main objective is to assess the extent to which “health resistance” differs amongst these samples. In addition, the paper provides further clarification of the concept of “health resistance”. The HR scale was distributed in the form of a questionnaire to two student samples, one from the University of Manchester, UK (n=167), the other from the University of Sydney, Australia (n=188). In each sample, students were selected from the three different faculties of arts, business and dentistry. Results from the random sample on which the original HR measure was developed are compared. Measures of health perception, health behaviours and psychological reactance were also obtained.

Details

Health Education, vol. 102 no. 6
Type: Research Article
ISSN: 0965-4283

Keywords

Article
Publication date: 5 July 2013

Youcef Zeroukhi, Ewa Napieralska Juszczak, Krzysztof Komeza, Fabrice Morganti and Guillaume Vega

In the majority of devices for measuring the resistance of wires or cables, the supplying voltage is applied via some clamping arrangement. Thus, current enters the bundle of…

Abstract

Purpose

In the majority of devices for measuring the resistance of wires or cables, the supplying voltage is applied via some clamping arrangement. Thus, current enters the bundle of conductors through the side surface of the outside wire. The purpose of this project was to establish the distance from the supplying point after which the current may be considered to be uniform and normal to the cable cross‐section.

Design/methodology/approach

When current passes from one wire to another, the crucial parameter is the resistance of the contact region. The paper presents a method by which this region can be identified and relevant resistance measured. A comprehensive simulation was conducted for different types of wires and cables to assess the influence of design parameters on the current distribution and uniformity.

Findings

The distance from the current entry point (the clamps) to the position where current density may be considered uniform has been established. This has facilitated estimating recommended positions of voltage taps with reference to current taps.

Practical implications

The look‐up tables and graphs allow adjustments to the position of the taps and/or correction of the measured results.

Originality/value

The original contribution of this paper is in the way the contact region is identified where current passes from one wire to another. Original relationships have been proposed showing the relationship between contact resistance and the design parameters of the cable and mechanical stress.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 7 June 2019

Grzegorz Tomaszewski, Jerzy Potencki, Grzegorz Błąd, Tadeusz Wałach, Grzegorz Gajór, Alena Pietrikova and Peter Lukacs

The purpose of this paper is to study the repeatability of path manufacturing in the drop on demand inkjet printing process and the influences of environmental and application…

Abstract

Purpose

The purpose of this paper is to study the repeatability of path manufacturing in the drop on demand inkjet printing process and the influences of environmental and application factors on path resistance.

Design/methodology/approach

Paths were printed as multiline paths in packets one-, two- and three-layer paths on polyimide substrates using nanoparticle silver ink. The sintering conditions were determined experimentally. The paths were subjected to climatic and shock exposures and to bending processes. The resistance, profile and width of the paths were measured and analyzed. The temperature distribution for electrically heated paths was measured to identify the defects.

Findings

This research shows the repeatability of printing processes and identifies the sources that cause diversification in path parameters after the whole technological process. The influence of shock, climatic and mechanical exposures on path electrical properties is indicated. An effective method for identifying defects thermally is shown.

Research limitations/implications

The research could have limited universality by arbitrarily use of substrate material, ink, printhead, process parameters and kind of sample exposures.

Practical implications

The research includes practically useful information about the width, thickness, defects and resistances and their changes during a typical application for a path printed with different technological parameters.

Originality/value

This research presents the results of original empirical research on problems concerning the manufacture of paths with uniform parameters and shows how path parameters will change under exposures that may occur in a typical application. The research combines both production and application aspects.

Details

Circuit World, vol. 45 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 23 October 2018

Yumiao Chen and Zhongliang Yang

Investigating the subjective breathing resistance of wearing respirators requires a valid and reliable technique to measure breathing resistance. The purpose of this study is to…

Abstract

Purpose

Investigating the subjective breathing resistance of wearing respirators requires a valid and reliable technique to measure breathing resistance. The purpose of this study is to test the validity and reliability of several rating scales and select the best for investigation of breathing resistance.

Design/methodology/approach

The authors designed three scales, that is, BRX scale, CP-100 scale and RVAS scale, and 30 subjects were separated into three groups, each group with a different scale. They sat for 5 min and walked for 5 min while wearing three models of respirators. After each trial, subjects were asked to complete subjective ratings of breathing resistance. Reliability was examined by the coefficient of Cronbach’s α, and validity was examined through content validity, discriminant validity and criterion validity. Generally, subjects were capable of reporting their sensation of breathing resistance by using the rating scale technique. However, the accuracy of rating strongly depended upon the properties of the scale.

Findings

The CP-100 scale was found to be highly reliable and most valid for rating subjective breath resistance. The validated CP-100 scale is very sensitive and accurate.

Originality/value

This is the first paper to select the best subjective scale for investigation of breathing resistance of respirators. The CP-100 scale will find wide applications in subjective breathing resistance evaluation for the use of respirators in industrial benchmarking activities. It will introduce the human factor engineering into the respirator manufacturing to improve the comfort of respirators.

Details

Journal of Engineering, Design and Technology, vol. 16 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 August 1930

H.M. Garner and L.P. Coombes

PROGRESS in most branches of engineering has been dependent upon model tests, and in no branch has the testing of models been of greater importance than in that of aeronautics…

Abstract

PROGRESS in most branches of engineering has been dependent upon model tests, and in no branch has the testing of models been of greater importance than in that of aeronautics. The earliest flights were made on models; and after the first successful flight of the full‐sized aeroplane, the development of aircraft to their present state of efficiency has been bound up, at every step, with the information obtained from model tests.

Details

Aircraft Engineering and Aerospace Technology, vol. 2 no. 8
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 September 2022

Fei Sun, Haisang Liu, Yuqin Din, Honglian Cong and Zhijia Dong

The purpose of this research is to propose a flexible sensor with a weft-knitted float stitch structure and to explore knitting techniques that allow conductive yarns to be…

Abstract

Purpose

The purpose of this research is to propose a flexible sensor with a weft-knitted float stitch structure and to explore knitting techniques that allow conductive yarns to be skin-tight and less exposed, reducing production processes and increasing productivity. Study its electrical conductivity in different yarn materials, knit processes and deformation ranges. The analysis is compared to provide some basis for the design of the electrodes.

Design/methodology/approach

The method includes five operations: (1) Analysis of the morphological appearance, tensile variation, fiber material properties and electrical conductivity of high-elastic and filament silver-plated conductive yarns. (2) Based on the knitting process of the floating yarn structure, three-dimensional modeling of the flexible sensor was carried out to explore the influence of knitting process changes on appearance characteristics. (3) The fabric samples are knitted by different silver-plated conductive yarns with different structures. Processing of experimental samples to finished size by advance shrinkage. (4) Measure the resistance of the experimental sample after the machine has been lowered and after pre-shrinking. Use the stretching machine to simulate a wearing experiment and measure the change in resistance of the sample in the 0–15% stretching range. (5) Analyze the influence factors on the conductive performance of the flexible sensor to determine whether it is suitable for textile flexible sensors.

Findings

For the float knitted flexible sensors, the floating wire projection is influenced by the elasticity of the fabric and the length of the floating wire. Compared to the plain knitted flexible sensors, it has less resistance variation and better electrical properties, making it suitable for making electrodes for textile structures. In addition, the knitting method is integrated with the intelligent monitoring clothing, which saves the process for the integration of the flexible sensor, realizes positioning and fixed-point knitting.

Practical implications

The sensor technology of the designed weft-knitted float structure is varied and can be freely combined and designed in a wide range. Within the good electrical conductivity, the flexible sensor can realize integrated knitting, positioning monitoring, integrating into the appearance of clothing. It can also focus on the wearing experience of wearable products so that the appearance of the monitoring clothing is close to the clothes we wear in our daily life.

Originality/value

In this paper, an integrated positioning knitting flexible sensor based on the weft knitting float structure is studied. The improved knitting process allows the sensing contact surface to be close to the skin and reduces the integration process. The relationship between the exposure of the silver-plated yarn on the clothing surface and the electrical conductivity is analyzed. Within a certain conductive performance, reduces the exposed area of the conductive yarn on the clothing surface and proposes a design reference for the flexible sensor appearance.

Details

International Journal of Clothing Science and Technology, vol. 35 no. 4
Type: Research Article
ISSN: 0955-6222

Keywords

1 – 10 of over 47000