Sensor-based monitoring systems

Development of microfluidics-based systems wifii small sample volumes and reduction of extensive sample cleanup requirements prior to analysis Need for well defined biochemical markers of quality for a variety of foods Low cost sensor-based analytical systems with automatic monitoring and reporting, e.g., via wireless-based systems Regulatory Agency approval for use of sensor technologies... 

Keeping in mind the nominal requirements for cGMP compliance requirements for lab-based instruments for demonstrating calibration (checking, adjustments, accuracy, precision, and traceability), what are some of the capabilities that will need to exist for process sensors or monitoring systems, and how will they be calibrated ... 

An important demonstrated application of this artificial nose system is the high-speed detection of low levels of explosives and explosive-like vapors. Several sensors, based on Nile Red attached to silica microspheres, show high sensitivity to nitroaromatic compounds (NAC) within a mixture12. Different fluorescence response profiles were observed for several NAC s, such as 1,3,5-trinitrotoluene (TNT) and 1,3-dinitrobenzene (DNB), despite their similar structures. These responses were monitored at low concentrations of the NAC vapors (ca. 5 ppb) and at short vapor exposure... 

Simply, SCADA is a computer-based control system that remotely controls processes previously controlled manually. The philosophy behind SCADA control systems can be summed up by the phrase, If you can measure it, you can control it. SCADA allows an operator using a central computer to supervise (control and monitor) multiple networked computers at remote locations. Each remote computer can control mechanical processes (mixers, pumps, valves, etc.) and collect data from sensors at... 

In order to implement frequency domain based sensing systems capable of monitoring the temporal luminescence of sensors, in few seconds, data must be collected at multiple frequencies simultaneously. Single-frequency techniques have been used to make frequency domain measurements of luminescent decays. 14, 23 28) This approach is unsuitable for real-time applications since data must be acquired at several frequencies in order to precisely and accurately determine the temporal variables of luminescent systems. 1 Each frequency requires a separate measurement, which makes the single frequency approach too slow to monitor the evolution... 

Emission lifetime provides a powerful selectivity dimension as each fluorophore has a unique decay rate. While laboratory fluorescent lifetime measurement systems are widely available and the concept of lifetime LIF sensing has been demonstrated,commercial LIF lifetime sensors are not yet available on the market for PAT and field applications to monitor organic analytes or bioagents. Once available, lifetime LIF sensors could revolutionize fluorescent based monitoring by affording superior detection merits along with sufficient recognition power. 

Figure 15 shows the schematic diagram of a typical sensor system. The CTL-based sensor element is fixed with pins to connectors for heater lead and thermocouple in the sensor cell. The temperature of the sensor is monitored by the thermocouple and is controlled by a digital temperature controller. The sample gas in the sensor cell is aspirated by an air pump downstream of the... 

Figure 10.1 contains an illustration of an implanted fluorescence-based sensor assuming the implanted materials and monitoring system can be designed to have each of the properties described above, this configuration is ideal, as it does not require any transdermal connections or implanted electronics. 

We propose signal processing of the UVP output. The gas-liquid interface is detected without using the echo intensity or any optical information. The method presented in this section represents an intermediate and necessary step in the development of an ultrasound-based sensor for reducing frictional drag. In the near future, a complete monitoring system for a bubbly two-phase boundary layer is to be developed. The system is to be applied to ships and pipelines. 

In the field of environmental works W. Bourgeois et al. developed a sensor array based measurement system for continuous monitoring of water and waste water. They tested an on-... 

The fact that the organotin carriers were proven to be anion selective in their neutral form provided the required information for the development of an optical sensor. Based on the coextraction principle, an optical sensor membrane for the determination of chloride was described. For this, tri-n-octyltin chloride was used as the ionophore, and together with the appropriate pH sensitive chromoionophore, allowed for the development of an optical sensor system for the monitoring of chloride levels in blood and serum. 

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