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Within the framework of image reconstruction in cylindrical electrical capacitance tomography (ECT) sensors, the purpose of this study is to select the structure of a sensor in terms of number and size of the electrodes, to predict the radius and the position of a single circular shape lying in the cross-section defined by the sensor electrodes.

Nonlinear black-box models using a set of physically independent capacitances and least-square support vector machines models selected with a sophisticated validation method are implemented.

The coordinates of circular shapes are well estimated in fixed and variable permittivity environments even with noisy data. Various numerical experiments are presented and discussed. Sensors formed by three or four electrodes covering 50 per cent of the sensor perimeter provide the best prediction performances.

The proposed method is limited to the detection of a single circular shape in a cylindrical ECT sensor.

This method can be advantageously implemented in real-time applications, as it is numerically cost-effective and necessitates a small amount of measurements.

The contribution is two-fold: a fast computation of a circular shape position and radius with a satisfactory precision compared to the sensor size, and the determination of a cylindrical ECT sensor architecture that allows the most efficient predictions.

The purpose of this paper is to describe a system that provides the driver or the driving assistance system with the lateral position information of the vehicle on the lane in order to detect as early as possible run‐off‐road and then prevent a foreseeable crash.

A magnetized tape deposited on the road in the middle of the lane generates a magnetic field which is detected by on‐board sensors. Depending on the distance between the tape and the sensors, accurate positioning information can be estimated.

The use of at least five sensors makes it possible to obtain a 2 mm‐lateral‐positioning accuracy.

Magnetized tapes are relatively cheap to install and provide an accurate vehicle lateral positioning with low ‐cost magneto‐resistance on‐board sensors. In addition , a magnetization variation along the tape would allow information to be coded which could be then transmitted to the driver.

The purpose of this paper is to introduce a rapid method for calculating capacitive sensor signal variations for any small permittivity or electrode modifications at any position in space.

When a capacitive sensor is probing its surrounding, the modification of the permittivity, the displacement or the deformation of one or more electrodes induce a signal variation which depends on the position of the modification. Seeing that modification as a small perturbation and using Gauss identity, it is possible to find integral expressions of the sensor sensitivity map.

Capacitive sensor sensitivity map expressions depend only on the perturbation to measure, on the electric field before the perturbation, and on a sensitivity field which is the electric field produced by the sensor when the measuring electrode is held to 1 V while the others, except the floating ones, are grounded. The sensitivity field is a kind of Green's function for the capacitive sensor. The knowledge of the electric and sensitivity fields makes it possible to obtain the whole sensor sensitivity map at once without requiring time consuming parametric calculations.

The sensitivity field calculation provides a simple and direct view of the capacitive sensor capabilities. That should improve capacitive sensor design.

On‐board absolute speed sensors would be very useful in automotive applications in order to perform the measurement of the speed independently of the wheel rotation. Narrow beam Doppler sensors give a good accuracy but only operate if there is a reflecting obstacle in the antenna footprint on the road. Broad beam Doppler sensors have the advantage of offering a higher probability of getting a reflected wave, but they require multiple frequencies. A novel sensor is presented. It uses a single frequency emission, which leads to low cost devices. Simulations and measurements have been carried out which show that it is particularly well adapted to high‐risk situations, for instance icy or very wet road surfaces, when only a few reflecting obstacles are present. In such situations, the accuracy of the measurement is typically of the order of 0.5 per cent.

Crude oil separation is an important process in the oil industry. To make efficient use of the separators, it is important to know their internal behaviour, and to measure the levels of multi‐interfaces between different materials, such as gas‐foam, foam‐oil, oil‐emulsion, emulsion‐water and water‐solids. To develop a multi‐interface level sensor.

Multi‐modality sensor with segmented capacitance and electromagnetic sensing elements. Some key issues are addressed, including the effect of salt content in water on measurement.

Working with gas/oil/saline water, the simulation and experimental results show that the newly designed sensor is promising.

First time to present this multi‐modality sensor, which can cope with current problems with saline water.

The Federal Motor Vehicle Safety Standards No. 208 includes directives rendering the morphological estimation of passengers mandatory for advanced air bag systems. The dynamic automatic suppression system uses both the morphological and positional information about the passenger to allow or prevent air bag deployment. Various solutions have been proposed to obtain these information by using capacitive sensors. This paper presents a method, that makes possible use of such sensors in the car industry by correcting their responses from these perturbing parameters.

To examine the sensors and techniques used in preventing the collision of moving vehicles.

A review of automobile‐guidance research projects carried out in European universities and advanced safety vehicle development by Japanese car manufacturers is followed by a description of driver assistance systems in current use. A new research initiative for autonomous unmanned aircraft is then discussed.

Fully‐autonomous prototype vehicles have demonstrated impressive feats on public roads, but car manufacturers are currently concentrating on driver assistance systems. Research is underway to extend the use of unmanned aircraft into the civil field, and to allow them to share airspace with piloted planes.

Presents current policies in automotive and aerospace development, and describes the range of sensor technologies applied to collision avoidance.

Examines the wide range of liquid and solid level sensors, their technologies and commercial application.

Provides background information on trends in level sensing, on how each type works and the various applications. Some selection criteria are given.

There is a wide range of level sensors for every target liquid and solid sensing application, but the sector is technologically mature. There are some new application areas deriving from legislation and climate change.

Provides information of value for those involved with sensor applications.

To expose the gate of ion‐sensitive field‐effect transistor (ISFET) to filthy and muddy water, suspended algae, etc. investigate the influence of these conditions on device performance and suggest measures for using the device in applications where suspended soil particles are present.

In this paper, cleaning procedure to make the blocked ISFET operative has been described. The effect of dirty water on pH sensitivity factor of ISFET, after it restarted functioning, has been measured. ISFET package has been modified. A relatively simple disposable nylon mesh with openings of size 100 μm for filtering bigger particles and lower for smaller particles, has been proposed for dirty applications to minimize device failures. This sieves away any dirt and thereby avoids failure.

The device action is frequently blocked by deposition of dirt on the gate. Generally, it is recoverable by proper cleaning action although with reduced sensitivity. This necessitates recalibration. But a protective filter helps in reducing failures. It is more advantageous to prevent clogging of ISFET than to revive a clogged device, sacrificing sensitivity.

After recovery, the original sensitivity of the device is not achieved, and the device has to be used with degraded sensitivity.

Measurement of pH of actual sources of water, whether clean or dirty, is important.

Problems of pH measurements of dirty samples have been studied. The study helps in understanding device behaviour in these samples and provides suitable corrective measures. Further, the pH survey of dirty and clean water samples provides useful information about the pH distribution and balance in nature.