Sensor scheduling

Keywords Radar sensor scheduling waveform beam-shape control detection tracking revisit time myopic non-myopic. 

Here we discuss simulations for sensor scheduling problems over up to two epochs into the future. The difficulties here reside in the design of the cost function and tracking of the scene. Our aim here is to show that sensor scheduling does, at least in simulation, achieve performance improvement. 

Scheduling is then done to permit a full scan over the prescribed scan period while also satisfying the constraints imposed by the revisit times obtained by the sensor scheduler. Once a target is measured, its revisit time is re-calculated. 

MoLoughlin, T, and M. Campbell. 2007. Scalable GNC architecture and sensor scheduling for large spacecraft networks. AIAA Journal of Guidance, Control, and Dynamics 30(2) 289-300. 

Matrix acidizing treatments are more often performed, nowadays, with sensors and data acquisition systems continuously recording the surface pressure and rate histories. According to a recently proposed methodology (15), these records can be used to compute downhole rate and pressure evolutions. The bottomhole pressure history is then compared to the theoretical response of an equivalent reservoir wherein a non-reactive fluid would have been injected according to an identical rate schedule. Following this method, the difference between both theoretical and actual pressure responses originates from the evolution of the skin of the true reservoir under the influence of the acid attack. Equation 1 is then used to derive the skin decrease from this pressure difference. 

D. Tian and N. D. Georganas, A coverage-preserving node scheduling scheme for large wireless sensor networks, Proceedings of the First ACM International Workshop on Wireless Sensor Networks and Applications, Atlanta, USA, September 2002, pp. 32-41. 

Waveform Scheduling The choice of measurement is made using the control variable n(k). In fact two choices are made at each epoch, the target to be measured and the waveform used. The waveforms impinge on the measurement process through the covariance matrix of the noise In this model, the sensor is characterised... 

We have compared one-step and two-step ahead scheduling using two performance measures. The first is the root mean square error of the track estimation this is a fairly obvious measure of the performance of the tracker. The second measure was the number of track updates. Since the sensor is managed in such a way that track updating is done only when the predicted track error exceeds a threshold, this also gives a measure of how far the estimation process is diverging from the actual target state. 

Finally in this section on simulations, we briefly describe a project that includes many of the ideas we have presented already. The crucial problem is to use scheduling to reduce the amount of time spent on tracking known targets while retaining a given level of track accuracy. By doing this we permit the sensor to spend more time in surveillance for new targets. 

The scheduling has a subtle effect on the lifetime of the sensor network. The lifetime depends on the actual amount of charge that can be drawn from the battery. The effective amount of charge is a result not only of battery s capacity, but also of the temperature and the rate of discharge [Ben 00, Ben 01]. Furthermore, a battery can recover some of its deliverable charge when... 

There is also a prototype of a Raman sensor module scheduled and in future a miniature spectrometer as shown in Figure 4.71 could be integrated [119]. 

A thin layer (approximately 10 mil thick) of RTV silicone was coated on the Micromet mini-dielectric sensor. The RTV silicone was first cured at room temperature, then in an oven at 120 C for a period of time, similar to certain RTV production cure schedules. The permittivity and loss factor of the RTV silicone were recorded during this cure cycle. 

The committee s assessment derives from the fact that the risk from asymmetric, or at least unconventional, attacks has increased. A determined adversary with even a small quantity of chemical or biological agent and a well-executed attack plan could produce significant consequences if supply chains, civilian support operations, and/or deployment schedules were disrupted. For example, the contamination of a ship in a foreign port raises the question as to how a captain should best utilize the non-medical science and technology at his disposal in response to an attack in which no sensor system allowed the avoidance of exposure. The extension of that question for the Non-Medical Science and Tech-... 

Install preventive maintenance monitoring equipment (e.g., vibration monitors, torque sensors) to optimize maintenance schedules. 

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