Sensor placement

Analysts must recognize the above sensitivity when identifying which measurements are required. For example, atypical use of plant data is to estimate the tray efficiency or HTU of a distillation tower. Certain tray compositions are more important than others in providing an estimate of the efficiency. Unfortunately, sensor placement or sample port location are usually not optimal and, consequently, available measurements are, all too often, of less than optimal use. Uncertainty in the resultant model is not minimized. 

S. S. Dhillon and K. Chakrabarty, Sensor placement for effective coverage and surveillance in distributed sensor networks, in Proceedings of the IEEE Wireless Communications and Networking Conference, New Orleans, USA, March 2003, pp. 1609-1614. 

Sensors are distributed equally in various areas of the stability chamber no less than 2 inches from any wall. A set of sensors should be placed near or at the temperature and/or humidity controller of the chamber, as the controller will maintain the set-point temperature and/or humidity within the chamber during normal use. For a typical walk-in chamber, a minimum of 24 thermocouples and six resistance-transmitting devices are recommended for use in the mapping study. For a benchtop or reach-in chamber, a reduced number of sensors may be used. It is important to note that regardless of the size of the chamber, the placement pattern of the sensors should be such that any potential hot or cold spots are mapped, particularly those areas near the door and comers of the chamber. Typical sensor placement patterns for a reach-in and walk-in chamber are shown in Figures 16.1 and 16.2, respectively. In these examples, the extremities of the chamber (i.e., top and bottom) have a larger number of sensors than the middle of the chamber, since these areas would have a greater probability of either hot or cold spots, due to the airflow pattern within the stability chamber. 

Figure 16.1. Typical sensor placement pattern for a reach-in stability chamber.

Antoniades, C. and Christofides, P. D. (2001). Integrating nonlinear output feedback control and optimal actuator/sensor placement for transport-reaction processes. Chem. Eng. Sci., 56, 4517-4535. 

Invest in high-fidelity modeling of releases in and near ports and bases to guide sensor placement and to form the basis for simplified operational tools. 

Dr. Swain also developed a simple method for visualizing the motion of gases from a hydrogen leak, which will be used to determine sensor placement for hydrogen leak detection. 

Task B - Development of Method to Determine Hydrogen Sensor Placement... 

Physiological measurement Textile-integrated sensors Signal source Typical sensor placement... 

Selection of appropriate electrode/sensor type and electrolyte, electrode /sensor placement, leads and cotmecfions (wiring). 

Keywords ambient vibration correlation function Duffing oscillator hydraulic jump information entropy modal identification optimal sensor placement spectral density structural health monitoring Wishart distribution... 

The present formulation for optimal sensor placement in terms of the information entropy provides a rational procedure for comparing the uncertainty of the estimates of the parameter values for different sensor configurations. Specifically, a direct measure of the uncertainty reduction is provided by the change of the information entropy ... 

Yuen, K.-V, Katafygiotis, L. S., Papadimitriou, C. and Mickleborough, N. C. Optimal sensor placement methodology for identification with unmeasured excitation. Journal of Dynamical Systems, Measurement and Control (ASME) 123(4) (2001), 677-686. 

From these eausal paths, the components involved in the residuals r and ra are obtained as Ki = [Qp, Ti, Vt, -Pi, P2] and K2 = [Vb, P2, Vo, Pi, P2], respectively. The fault signatures obtained from causal path analysis are identical to the ones obtained before (Table 7.3). Thus, sensor placement problem is reduced to a... 

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