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This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

The GMI sensor contains a Co-based internal magnetic core fabricated by laser cutting and an external solenoid. The influences of magnetic permeability of magnetic core and structure parameters on GMI effect were calculated in theoretical model. The output impedance, resistance, reactance and GMI ratio were measured by non-contact method using impedance analyzer.

Enhancing external magnetic field intensity can decrease the magnetic permeability of core, which has vital influences on the magnetic property and the output response of GMI sensor. In addition, increasing the width of magnetic core and the number of solenoid turns can increase the maximum GMI ratio. The maximum GMI ratio is 3,230% with core width of 6 mm and solenoid turns of 200.

Comparing with traditional contact-measured GMI sensor, the maximum GMI ratio and the magnetic field sensitivity are improved and the power consumption is decreased in non-contact measured GMI sensor. GMI sensor measured by non-contact method has a wide range of potential applications in ultra-sensitive magnetic field detection.

The introduction of time compression technologies into the modern mechanical design process is now well established. Most major automotive and aerospace companies have invested, as have their Tier 1 suppliers. It has been identified that a bottleneck affecting all aspects of the cycle is the measurement process. In this paper we shall discuss potential benefits of adopting non‐contact techniques. In section 1 we discuss the need for rapid physical measurement within the context of the mechanical design process. The processes required for surface creation and inspection are discussed in Section 2 with regard to contact and non‐contact measurement. Section 3 reviews the operating principles of commercially available non‐contact systems. Finally Section 4 discusses practical issues relating to the implementation and use of non‐contact systems in the manufacturing environment.

A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as semi‐rigid material) and non‐rigid material (woven fabric). This end‐effector operates on the principle of generating a high‐speed air flow between nozzles and the specimen surface thereby creating a vacuum which levitates the materials with no mechanical contact. In this paper, the handling results of these materials are compared with each other. The changes in the physical behavior of lifting materials were observed during the experimental work. The effect of the various air flow rates on the non‐contact handling clearance gap between the nozzle and the materials were also investigated. As a result, it was observed that the non‐contact end‐effector could be applied to handle different flat materials.

The purpose of this paper is to determine the extent to which mental health, physical health, communication, learned function of the behaviour(s), severity of disability, living arrangement, age, and gender, alone or in combination, predicted challenging behaviours in adults with intellectual disability.

In total, 74 adults with intellectual disability and their paid carers were recruited into the study from adult disability services in Victoria, Australia. Paid carers provided information about participants with intellectual disability on a range of measures targeting each variable of interest.

Based on principle components analyses of three challenging behaviour measures, two topographies of challenging behaviour emerged: contact and non-contact behaviours. Multiple regression analysis revealed that contact behaviours were predicted by anxiety scores and severity of disability. In addition to severity of disability and anxiety scores, non-contact behaviours were also predicted by sensory scores.

The results of the current study indicate that contact and non-contact behaviours were determined by multiple factors. Clinicians and others who work with people who display challenging behaviour may, therefore, find it helpful to utilise the biopsychosocial model in their formulations of possible reasons that motivate a person to engage in challenging behaviour.

These results contribute to the evidence base available to clinicians and researchers to guide future assessment for challenging behaviour. Expansion of functional assessment methods to explore factors not traditionally included, such as mental health and severity of intellectual disability, as causes of challenging behaviour, may prove helpful.

Varied shapes and sizes of different products with irregular rough surface and fragile properties give a challenge to traditional contact gripping. Single Bernoulli grippers are not suited to handle fragile objects as the impact of center negative pressure force could result in large deformation and stress which damage the materials, and they are also have some limitations for gripping objects with different large and small shapes. Thus, this paper aims to design a non-contact gripper for soft, rough-surfaced and fragile objects gripping with multi Bernoulli heads, which have optimal structures and parameters.

The compressed air is ejected into four Bernoulli heads through radial and long flow channels, then passes through four strip-shaped narrow gaps after fully developing in the annular cavity to provide negative pressure. Based on the mathematic model and the computational model, the key structural parameters affecting the gripping performance are selected, and parameters optimization of the gripper is performed by computational fluid dynamics simulation analysis and performance evaluation. The orthogonal method is used and L16 orthogonal array is selected for experimental design and optimization. The characteristics of the designed gripper are tested from the aspects of pressure distribution and lifting force.

From the applications in gripping different objects, the designed non-contact gripper can grip varied shapes and sizes of soft, rough-surfaced, fragile and sliced objects with little effect of torque.

In this paper, a non-contact gripper is designed for handling soft, rough-surfaced and fragile objects based on the Bernoulli principle. A systematic approach, which consists of modeling, simulation, optimization and measurement is provided for the non-contact gripper design and tests.

Looks at the use of non‐contact displacement and vibration sensors and notes their value for difficult sensing measurements. Mentions various situations which may dictate the use of a non‐contact sensor. Focuses on fibre‐optic sensors and laser triangulation sensors. Concludes that practical uses for such devices are rapidly expanding.

A new type of hydrostatic and hydrodynamic non-contacting face seals has been designed to meet the requirements of lower leakage, longer life and more repeatedly start and stop on shaft seals raised by liquid rocket engine turbopumps. And an experimental study on the performance of the face seal in the actual liquid oxygen turbopump was completed where low-viscosity water was selected as the seal fluid for the sake of safety. The paper aims to discuss these issues.

Different performances of face seals under preset conditions were obtained by repeatedly running tests, and the main performance parameters encompass leakage, fluid film pressure between the faces, operating power, face temperature, and so on.

The results indicate that the designed face seal has a smaller amount of leakage, with a minimum value of 3 ml/s. Furthermore, the designed face seal has been proved to demand lower operating power. Since its operating power changes slightly with different sealed fluid pressures, the new seal can be deployed in the harsh working condition with high pressure or with high speed (greater than 20,000 rpm). However, one proviso is that when liquid is employed as the seal fluid, the groove depth should be relatively deeper (greater than 10 μm).

In response to future engineering requirements, study on the controllable spiral-groove face seals to improve the current design is being conducted.

The advancement of such non-contacting face seals proffers important insights to the design of turbo-pump shaft seal in a new generation of liquid rocket engine with regard to the requirement of frequent start and stop as well as long life on it.

In many instances measurement equipment which makes contact with the media or product provides inaccurate results owing to corrosion, mechanical damage or a build‐up of the monitored production on the sensor. In view of the possible deleterious effects it is better to operate a non‐contact method of monitoring, especially in the food and pharmaceutical industries. This produces greater reliability coupled with lower maintenance. The infinite possibilities of non‐contact options require expertise in inductive, capacitative, photoelectric, infrared and ultrasonic measurement and control technology.

The conventional strain gauge type pressure sensor suffers in static testing of engines due to the contact transduction method. This paper aims to focus on the concept of non-contact transduction-based pressure sensor using eddy current displacement sensing coil (ECDS) to overcome the temperature limitations of the strain gauge type pressure sensor. This paper includes the fabrication of prototypes of the proposed pressure sensor and its performance evaluation by static calibration. The fabricated pressure sensor is proposed to measure pressure in static test environment for a short period in the order of few seconds. The limitations of the fabricated pressure sensor related to temperature problems are highlighted and the suitable design changes are recommended to aid the future design.

The design of ECDS-based pressure sensor is aimed to provide non-contact transduction to overcome the limitations of the strain gauge type of pressure sensor. The ECDS is designed and fabricated with two configurations to measure deflection of the diaphragm corresponding to the applied pressure. The fabricated ECDS is calibrated using a standard micro meter to ensure transduction within limits. The fabricated prototypes of pressure sensors are calibrated using dead weight tester, and the calibration results are analyzed to select the best configuration. The proposed pressure sensor is tested at different temperatures, and the test results are analyzed to provide recommendations to overcome the shortcomings.

The performance of the different configurations of the pressure sensor using ECDS is evaluated using the calibration data. The analysis of the calibration results indicates that the pressure sensor using ECDS (coil-B) with the diaphragm as target is the best configuration. The accuracy of the fabricated pressure sensor with best configuration is ±2.8 per cent and the full scale (FS) output is 3.8 KHz. The designed non-contact transduction method extends the operating temperature of the pressure sensor up to 150°C with the specified accuracy for the short period.

Most studies of eddy current sensing coil focus on the displacement and position measurement but not on the pressure measurement. This paper is concerned with the design of the pressure sensor using ECDS to realize the non-contact transduction to overcome the limitations of strain gauge type pressure sensors and evaluation of the fabricated prototypes. It is shown that the accuracy of the proposed pressure sensor is not affected by the high temperature for the short period due to non-contact transduction using ECDS.

This article presents an application of survey non-response theory to a specific population with disabilities. From 1994 to 1997 the U.S. National Health Interview Survey (NHIS) did a special, two-phase study of disability. This survey format allowed for response patterns of the disabled population to be operationalized into contact, cooperation and proxy/assisted versus self-response categories. Using these data, the authors investigated the effects of severity of activity limitation at first interview on response patterns at second interview, with statistical controls for other characteristics related to the response outcome. The statistical results of the study show that respondents with moderate or severe activity limitation are more likely than those with mild activity limitation to be contacted and to cooperate, yielding higher response rates. However, respondents with a higher degree of activity limitation are also more likely to have proxy/assisted responses at re-interview. Barriers to self-response in household surveys are discussed in the concluding remarks.