Passive sensing

Optical fibre based optical detection systems offer a number of advantages over bulk optical sensing systems. The principal one is that a robust passive sensing head may be remoted from the monitoring station a factor giving particular advantages in severe environments. This also allows... 

Passive heat-transfer enhancement techniques, retrofitted, 13 267 Passive mixers, in microfluidics, 26 966, 967 Passive noise detectors, 11 673 Passive nondestructive tests, 17 416, 425 Passive reactors, 17 555 Passive sensing materials, 22 706-707 Passive smart textiles, 24 625 Passive solar collection, silica aerogel application, 1 761-762 Pasta products, 26 278 Paste-extrusion process, 18 301-302 Paste forming, ceramics, 5 651 Paste inks, 14 315-316... 

Regarding (b) to locate a physical object by its smell, we normally have to determine the odor s direction. But as we have seen, to make that determination we, in turn, have to move our heads and track intensity gradients it cannot be done phenomenologically, in my passive sense of "phenomenology." ... 

Passive sensing SHM is done by using sensors to just listen to stmctural signals and monitor them over time. The premise of strain SHM is that presence of damage will effect a redistribution of mechanical strain in the stmcture, which can be monitored and interpreted. A sudden rise of strains in a safety-critical part of the structure should... 

Another model-free method for active damage detection is based on directional transducers. For passive sensing. Section 16.9 has already discussed the use of directional strain rosettes (both piezo and optical) to effectively detect an acoustic source without the need for a structural model. For active sensing, directional transmission as well as reception of guided wave can be achieved with phased-array transducers. 

Markmiller JFC, Chang FK. Sensor network optimization for a passive sensing impact detection technique. Struct Health Monit Int J 2010 9(1) 25—39. http //dx.doi.org/... 

Most machine vision systems rely on data captured by hardware with fixed characteristics. These systems include passive sensing systems—such as video cameras—and active sensing systems—such as laser range finders. In an active vision system, the parameters and characteristics of data capture are dynamically controlled by the scene interpretation system. Active vision systems may employ either active or passive sensors. In an active vision system, however, the state parameters of the sensors, such as focus, aperature, vergence, and dlumination, are controlled to acquire data that will faciKtate scene interpretation. 

Table 6.9. Most used EAP for passive sensing and conventional inorganic counterparts...

Fig. 4 (a) Detection of the pore blockade by reading the ionic current flowing through the nanopore, (b) Simplest current measuring scheme based on a passive sensing resistor R me and a voltage amplifier G. 

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