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This article describes a new humidity sensor using the technique of differential thermal analysis (DTA). The energy of water vaporisation is estimated via the measurement of the Seebeck voltage of miniature thermocouples used in differential mode on a Peltier module causing condensation from the ambient air. This sensor uses the sensitivity of alloys V2VI3 containing [Bi, Te, Sb, Se], 400‐440μV.K^–1. Experimental measurements have been performed in a climatic chamber at constant temperature. The time variation of the differential Seebeck voltage with relative humidities H_R varying from 10 to 90 per cent makes it possible to identify with precision the point of water evaporation. For each value of the relative humidity, it is directly a function of the condensate mass. The integration of these curves over time makes it possible to calculate the energy of vaporisation and the condensate mass.

In this work an original humidity sensor is described. It is based on the study of Seebeck voltage evolution during the water evaporation of a micro‐module Peltier (MMP). The measurement principle is to detect (after cooling) the small temperature decrease created when total water evaporation occurs over the MMP. All the active thin layers of the sensor are made from (Bi₂Te₃)_0.9(Bi₂Se₃)_0.1 (N) films and (Bi₂Te₃)_0.25(Sb₂Te₃)_0.75 (P) films flash evaporated. Experimental measures were performed in a climatic chamber for several values of relative humidity (50 to 90 per cent). The phenomenon (evaporation) appears after a delay time τ. This delay time is the response time of the sensor. Therefore it is possible to draw the evaporation delay time as a function of relative humidity.

In this paper, we propose a new way for the determination of a_w in fresh and salt meat. The principle is founded on the analysis of a small air volume inside the product. First we describe the fundamental definition of water activity, the state‐of‐the‐art of commercial a_w meters, the effects of a_w on microbiology in food. In the second step, after a description of the sensor, the principle and the procedure of measurement are explained. The measurements of a_w are realized in meat at different stages of drying. Reproducibility and the temperature effect are particularly analyzed.

The purpose of this paper is to apply a negative gate bias stress in order to study instabilities of threshold voltage in N‐channel power vertical double‐diffused metal‐oxide‐semiconductor field effect transistor (VDMOSFET). Variations in gate oxide trapped charge and interface trap densities are also calculated.

A threshold voltage shift is detected; the oxide and interface trap densities were evaluated based on a direct measurement of the gate to source capacitance and conductance.

Results presented show that the threshold voltage is decreasing with stress time, the capacitance and conductance curves are altered by applied stress, also the oxide traps and the interface traps densities are increasing with stress time.

The positive bias stress seems to be more destructive in the case of the studied devices.

This document presents the study of a one‐dimensional thermal inclinometer based on free convection.

A micromachined one is used. The sensitivity of the sensor is optimized in a close chamber containing CO2 gas under pressure.

By using this type of sensor in a close chamber containing CO2 gas under pressure, the sensitivity increase and the response time decrease when the pressure increase. High resolution will be achieved.

High shock reliability.

Measuring μg acceleration.

Low cost production.

The purpose of this paper is to present the dependence of capacitive sensing of organic vapours by porous silicon (PS) on its molecular structure for the realization of a organic vapour sensor, compatible with existing silicon technology, with desired miniaturization and selectivity.

The method introduces large surface area of PS obtained by electrochemically etching of silicon wafer for characterization of organic vapours through capacitive sensing.

The method provides a comparative study of sensor response for organic vapour molecules of different structures and leads to an insight into the sensing mechanism.

The surface of PS has been stabilized by thermal oxidation process.

The method is useful for the development of a simple, cost‐effective sensor for selective gas analysis.

The result is an outcome of regular experimental work carried out to observe the capacitive sensing behavior of PS for different organic vapours.

Sensor networks have found wide applications in the monitoring of environmental events such as temperature, earthquakes, fire and pollution. A major challenge with sensor network hardware is their limited available energy resource, which makes the low power design of these sensors important. This paper aims to present a low power sensor which can detect sound waveform signatures.

A novel mixed signal hardware is presented to correlate the received sound signal with a specific sound signal template. The architecture uses pulse width modulation and a single bit digital delay line to propagate the input signal over time and analog current multiplier units to perform template matching with low power usage.

The proposed method is evaluated for a chainsaw signature detection application in forest environments, under different supply voltage values, input signal quantization levels and also different template sample points. It is observed that an appropriate combination of these parameters can optimize the power and accuracy of the presented method.

The proposed mixed signal architecture allows voltage and power reduction compared with conventional methods. A network of these sensors can be used to detect sound signatures in energy limited environments. Such applications can be found in the detection of chainsaw and gunshot sounds in forests to prevent illegal logging and hunting activities.

This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on metamaterial for sensing application has led to the advancement of compact and improved sensors.

In this study, relevant research papers on metamaterial sensors for material characterization published in reputed journals during the period 2007-2018 were reviewed, particularly focusing on shape, size and nature of materials characterized. Each sensor with its design and performance parameters have been summarized and discussed here.

As metamaterial structures are excited by electromagnetic wave interaction, sensing application throughout electromagnetic spectrum is possible. Recent advancement in fabrication techniques and improvement in metamaterial structures have led to the development of compact, label free and reversible sensors with high sensitivity.

The paper provides useful information on the development of metamaterial sensors for material characterization.

This paper aims to give an overview about the state of the art and novel technologies used in gas sensing. It also discusses the miniaturization potential of some of these technologies in a comparative way.

In this article, the authors state the most of the methods used in gas sensing discuss their advantages and disadvantages and at last the authors discuss the ability of their miniaturization comparing between them in terms of their sensing parameters like sensitivity, selectivity and cost.

In this article, the authors will try to cover most of the important methods used in gas sensing and their recent developments. The authors will also discuss their miniaturization potential trying to find the best candidate among the different types for the aim of miniaturization.

In this article, the authors will review most of the methods used in gas sensing and discuss their miniaturization potential delimiting the research to a certain type of technology or application.

The purpose of this paper is to report the study of vibration energy harvesting from a data center (DC) mainframe computer to power nodes of a wireless sensors network (WSN are used to improve the energy efficiency of a DC).

The piezoelectric vibration energy harvester (VEH) has been designed using an electromechanical analytical model. The VEH is composed of a three-layer cantilever beam with a tip mass. A vibration map (amplitude and acceleration) is presented and the authors show that the optimum frequency is around 90 Hz with maximum amplitude of 1 μm and maximum acceleration of 0.6 m/s2. Modeling results and experimental measurements using an electromagnetic shaker to apply vibrations concord.

The VEH delivers a maximum power of 31 μW on a DC mainframe computer and 2.3 mW at 1g on a test rack. It allows us to use a storage capacitance to successfully power a wireless sensor node for measuring temperature. This paper has been carried out in cooperation with IBM Montpellier and within the framework of the RIDER project financed by the French government and the European Union.

A vibration map (amplitude and acceleration) is presented and the authors show that the optimal frequency is around 90 Hz with maximum amplitude of 1 μm and maximum acceleration of 0.6 m/s2. The VEH delivers a maximum power of 31 μW on DC mainframe computer and 2.3 mW at 1 g on test mounted the shaker. It allows us with a storage capacitance to successfully power a wireless sensor node for measuring temperature.