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This paper aims to review the current knowledge about the neutral component of the local interstellar medium (LISM), which due to the resonant charge exchange, photoionization and electron impact ionization processes has a profound impact on the heliosphere structure.

This work is based on the heliospheric literature review.

The summary of four major effects of neutral hydrogen atoms penetrating solar wind (SW), i.e. the disappearance of the complicated flow structure; the emergence of “hydrogen wall” in front of the heliopause (HP); decreasing distance of termination shock (TS), HP and bow shock (BS) layer from the Sun; and recently discovered by the Interstellar Boundary Explorer mission, a region of enhanced energetic neutral atom (ENA) emission seen in all sky maps as a ribbon.

In the context of constantly developing space technologies in aerospace engineering and prospective deep space missions, there is a need of general reviews about the interstellar space surroundings of the Sun and gathering the knowledge to help in theoretical, numerical and experimental investigations such as the optimization of the scientific equipment and spacecraft structure to work in specific conditions.

The survey encapsulate basic and relevant processes playing an important role in the physics of the nearest surroundings of the Sun and the latest results of numerical and experimental investigations focused on the neutral LISM component and its influence on the heliosphere, which is strongly desired in future works. Until now, not many of such reviews have been done.

The purpose of this paper is to provide a review of the industrial sensing applications of electromagnetic radiation (EMR) with an emphasis on wavelengths other than visible light. The paper is in two parts. This, the first, considers radiations with shorter wavelengths than visible light, i.e. γ radiation, X‐rays and ultra‐violet (UV).

The paper discusses the sensing applications of short wavelength EMR through reference to the techniques employed, products and their uses.

The paper shows that γ radiation, X‐rays and UV radiation are used in a wide range of industrial sensors for the measurement of physical variables, chemical compounds and gases. The phenomena employed include absorption, backscatter, photoionisation, fluorescence and reflection. Applications are extremely varied and embrace a diversity of industries.

The paper provides a detailed, technical review of the sensing uses of short wavelength EMR.

The aim of this paper is to develop and validate a model and a numerical code describing the laser matter interaction and also laser ablation. The laser wavelength is 193 nm and the pulse duration is several nanoseconds.

The developed model is based on strong theoretical background (cf. references). The electronic nonequilibrium aspect is always taken into account. The electronic nonequilibrium is one of the key aspect the UV laser matter interaction and must be treated carefully and that is not always the case. The numerical code was developed using efficient and versatile numerical methods. The model and simulations are always compared to experiments in order to validate them and also to find their limitations.

This work has greatly improved the code accuracy. The key role of the electronic nonequilibrium is also demonstrated. From experimental comparisons it is obvious that photo‐ablation should be taken into account for the lower fluences, but to do so, a completely new approach must be developed.

This work describes the whole laser ablation process with the electronic nonequilibrium effects properly modeled. The numerical results has always been confronted to experiments, in most of the cases the agreement was very good. When it was not the case, explanations have been sought along with ways to improve the approach.

Fineness‐of‐grind gauges This gauge is described by Sheen Instruments as one of the basic instruments used in the paint, printing ink and pigment trades. It is a hardened steel plate with either one or two channels ground into the top surface from zero depth to 100 µm, 0–50µm, or 0–25 µm.

This paper aims to provide details of the major optical gas sensing techniques and their applications.

Following an introduction, this paper first identifies the major gas sensing technologies and provides an overview of optical sensing techniques. The sources and impact of the gases most frequently sensed by optical methods are listed. Three non-absorption-based and nine absorption-based methods and their main applications are then described in detail. Brief concluding comments are drawn.

All manner of optical gas sensing techniques have been commercialised and while the majority are absorption-based, several other methods also play a significant role. Some optical gas sensors offer advanced capabilities such as remote monitoring, the creation of 2D and 3D distribution maps, detection of parts per trillion levels and even the visualisation of gases in real time. They play a vital role in protecting workers from hazardous gases, controlling and minimising air pollution and monitoring the atmospheric environment, as well as being used in the food, medical, process, power generation and other industries.

This paper provides a detailed insight into optical gas sensing techniques and their uses.

WE SEEM to accept noise in machinery as inevitable. If our forefathers came back to earth, apart from the frightening speed of everything, methods of transport and a hundred and one unbelievable ‘improvements’ to civilised living, we think it is the noise that they would find most difficult to withstand. Noise of transport, noise in a factory, and the apparently unconcerned attitude of those who are used to it. Modern medical science is now finding out that ears can be damaged by excessive noise, and certainly a great deal of it can be reduced if proper care is taken in machine design and maintenance. We believe that there is a society formed to consider these problems. Jet aircraft have roused many people to consider noise, but this is only one item.

Sensor arrays and pattern recognition-based electronic nose (E-nose) is a typical detection and recognition instrument for indoor air quality (IAQ). The E-nose is able to monitor several pollutants in the air by mimicking the human olfactory system. Formaldehyde concentration prediction is one of the major functionalities of the E-nose, and three typical machine learning (ML) algorithms are most frequently used, including back propagation (BP) neural network, radial basis function (RBF) neural network and support vector regression (SVR).

This paper comparatively evaluates and analyzes those three ML algorithms under controllable environment, which is built on a marketable sensor arrays E-nose platform. Variable temperature (T), relative humidity (RH) and pollutant concentrations (C) conditions were measured during experiments to support the investigation.

Regression models have been built using the above-mentioned three typical algorithms, and in-depth analysis demonstrates that the model of the BP neural network results in a better prediction performance than others.

Finally, the empirical results prove that ML algorithms, combined with low-cost sensors, can make high-precision contaminant concentration detection indoor.

This paper aims to provide details of miniaturised analytical instrument technologies and developments.

Following an introduction and historical background, this first considers miniaturised chromatographs and spectrometers based on micro-electromechanical system (MEMS)/micro total analytical system technologies. It then discusses lab-on-a-chip developments with an emphasis on capillary electrophoresis. Developments in the emerging lab-on-paper technology are then considered and are followed by brief concluding comments.

This shows that many classes of analytical instruments which offer a number of operational and economic benefits have been miniaturised through the use of microfabrication and other technologies. They are an active field of research and are based on silicon, glass, polymers and even paper and are underpinned by developments in microfluidics and optofluidics and fabrication techniques which include lithography, MEMS and micro-opto-electromechanical system.

This provides an insight into the rapidly developing field of miniaturised analytical instrument technologies.

The purpose of this paper is to provide details of recent developments in sensors for detecting explosives and chemical warfare agents.

Following an introduction, this paper first discusses a selection of new sensing techniques aimed at detecting explosives and explosive devices. It then considers new developments in sensors for detecting chemical warfare agents. Brief concluding comments are drawn.

This paper shows that a diversity of sensor technologies is being investigated, including various advanced optical methods, nanomaterials, microelectromechanical system, electronic noses, biosensors and electrochemical techniques, several of which offer levels of sensitivity in the parts-per-trillion region. These not only have the potential to yield improved devices for detecting explosives and chemical weapons but may also play a role in health care, environmental monitoring, drug detection and industrial health and safety.

In an era of escalating terrorism and military conflicts, this provides a timely review of new technologies for detecting explosives and chemical warfare agents.

The purpose of this article is to illustrate how sensors impart perceptive capabilities to robots. This is the second part of a two-part article. This second part considers positional awareness and sensing in the external environment, notably but not exclusively by autonomous, mobile robots.

Following a short introduction, this article first discusses positional sensing and navigation by mobile robots, including self-driving cars, automated guided vehicles, unmanned aerial vehicles (UAVs) and autonomous underwater vehicles (AUVs). It then considers sensing with UAVs and AUVs, and finally discusses robots for hazard detection. Brief concluding comments are drawn.

This shows that sensors based on a multitude of techniques confer navigational capabilities to mobile robots, including LIDARs, radar, sonar, imaging and inertial sensing devices. UAVs, AUVs and mobile terrestrial robots can be equipped with all manner of sensors to create detailed terrestrial and underwater maps, monitor air and water quality, locate pollution and detect hazards. While existing sensors are used widely, many new devices are now being developed to meet specific requirements and to comply with size, weight and cost restraints.

The use of mobile robots is growing rapidly, and this article provides a timely account of how sensors confer them with positional awareness and allow them to act as mobile sensing platforms.