France, sensor development

In some ways, this is the same requirement faced when developing electronic nose technology. Sensor-based electronic noses are based upon an array of non-specific gas sensors coupled with a pattern recognition technique (Gardner and Bartlett, 1999 Pearce et al, 2003). Electronic noses tend to be large, expensive instruments. For example, the Fox 4000 electronic nose (Alpha MOS, France) comprises 18 power-hungry Taguchi-like metal oxide resistive gas sensors (see Fig. 15.11). 

Recently we have developed a new Raman sensor devoted to road de-icing application. Thus, in winter a lot of salt is applied on roads as brine (NaCl solutions in France) in order to preserve the safety of users and traffic flow. However, conventional measurement techniques such as electrical conductivity are inaccurate and difficult to implement (time consuming and dangerous for operators). We have developed a prototype sensor using RS to measure remotely (< 5 cm) and quickly ( 1 sec) the NaCl concentration (0-200 g/1) on the road with an accuracy less than 5%. A second prototype allowing measurements on board a vehiele is still under consideration. 

A good survey of this field was presented by T. Takeuchi at the 2nd international meeting on chemical sensors in Bordeau, France, 1986. In Fig.7 some forms of the three types are presented along with the working principle, based on the paper mentioned. A SO2 sensor based on a similar principle has been developed by H. Torvela. The sensor produces a Nernstian response. 

Scott Fisher and Elizabeth Wenzel developed hardware for three-dimensional virtual sound sources in 1988. Also in the late 1980 s, Lanier built a virtual reality system for two simultaneous users that he named RB2 (Reality Built for Two). Fisher incorporated sound systems, head-mounted device technology, and sensor gloves into one system called the Virtual Interactive Environment Workstation (VIEW), also used by NASA. The first conference on virtual reality, Interfece for Real and Virtual Worlds, was held in Montpellier, France, in March, 1992. That same year, scientists, engineers, and medical practitioners assembled in San Diego, California, for the Medicine Meets Virtual Reality Conference. In September, 1993, the Institute for Electrical and Electronics Engineers (IEEE) organized its first virtual reality conference in Seattle. 

Asher, R.C. et al.. Recent Developments in the Design, Performance, and Application of Harwell Oxygen Sensors and Harwell Carbon Meters. Proceedings of the Fourth International Conference on Liquid Metal Engineering and Technology, Avignon, France, October 1988, 3, 602. 

This dynamic technique was initially developed by Mathonat and coworkers at University of Clermont-Ferrand (France). It is a flow technique where the heat of mixing is measured in a mixing cell located inside a Calvet type calorimeter (Fig. 14.5a). The Calvet sensors are a thermopiles constituted of thermocouples surrounding the mixing cell and measuring the heat power exchanged with a thermostated calorimetric block. The mixing cell represented in Fig. 14.5b consists of an hastelloy tube... 

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