Electromechanical analysis

A complementary technique to EQCM is to monitor volume changes during cyclic potential sweeps—electromechanical analysis (EM A). This method is based on work by Pei and Inganas143149 and has been further developed at IPRI (see Chapter 3). The 

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A. J. Bard and I. Rubinstein 1. Electromechanical analysis—Addresses, essays, lectures 1. Bard, Allen J., ed. 

FIGURE 1.25 Electromechanical analysis (EMA) data showing length changes (strain) during potential cycling of PPy/pTS. 

Encapsulating available knowledge into parametric models for electrical performance at radio frequencies (RF) enables the designer to predict insertion loss, return loss (reflection), and insertion phase and delay of the MEMS switch without time-consuming full-wave analysis in the same environment as used for the initial electromechanical analysis. 

Sarmento-Leite R, Silva GV, Dohman HF, Rocha RM, Dohman HJ, de Mattos ND, Carvalho LA, Gottechall CA, Perin EC. Comparison of left ventricular electromechanical mapping and left ventricular angiography defining practical standards for analysis of NOGA maps. Tex Heart Inst /2003 30 19-26. 

Three-dimensional (3D) structuring of materials allows miniaturization of photonic devices, micro-(nano-)electromechanical systems (MEMS and NEMS), micro-total analysis systems (yu,-TAS), and other systems functioning on the micro- and nanoscale. Miniature photonic structures enable practical implementation of near-held manipulation, plasmonics, and photonic band-gap (PEG) materials, also known as photonic crystals (PhC) [1,2]. In micromechanics, fast response times are possible due to the small dimensions of moving parts. Femtoliter-level sensitivity of /x-TAS devices has been achieved due to minute volumes and cross-sections of channels and reaction chambers, in combination with high resolution and sensitivity of optical con-focal microscopy. Progress in all these areas relies on the 3D structuring of bulk and thin-fllm dielectrics, metals, and organic photosensitive materials. 

Salzstein, R.A. and Pollack, S.R. (1987) Electromechanical potentials in cortical bone-II. Experimental analysis. Journal of Biomechanics 20 271-280... 

On the other hand, the heat fransfer literatiue of the last decade has demonstrated a vivid and growing interest in thermal analysis of flows in micro-channels, botii tiirough experimental and analytical approaches, in connection with cooling techniques of micro-electronics and witii tiie development of micro-electromechanical sensors and actuators (MEMS), as also pointed out in recent reviews [12-16]. Since tiie available analytical information on heat fransfer in ducts could not be directly extended to flows witiiin microch mels with wall slip, a number of contributions have been recentiy directed towards the analysis of internal forced convection in the micro-scale. In the paper by Barron et al. 

The performance of oscillators depends essentially on the stabihty of the acoustic device [7-9] no matter if working as electromechanical resonator or delay line. Because of its extraordinary importance we will concentrate further on resonators, namely quartz crystal resonators. However, the analysis is descriptive also for other piezoelectric materials and partly for delay line elements as well. 

Koh et al. [6] have rigorously modeled the electromechanics of this interaction for the simplified case of uniform biaxial stretching of an incompressible polymer film including many important effects such as the nonlinear stiffness behavior of the polymer film and the variation in breakdown field with the state of strain. With regard to the latter effect, Pelrine et al. [5] showed the dramatic effect of prestrain on the performance of dielectric elastomers (specifically silicones and acrylics) as actuators. We would expect the same breakdown enhancement effects to be involved with regard to power generation. There are many additional effects that may be important, such as electrical and mechanical loss mechanisms, interaction with the environment or circuits, frequency, and temperature-dependent effects on material parameters. The analysis by Koh provides the state equations... 

G.M. Spinks and V.-T. Truong, Work-per-cycle analysis for electromechanical actuators. Sens. Actuat A, A119 (2), 455 61 (2005). 

Humans in the system can be treated in the same way as automated components in step 1 of STPA, as was seen in the interlock system above where a person controlled the position of the door. The causal analysis and detailed scenario generation for human controllers, however, is much more complex than that of electromechanical devices and even software, where at least the algorithm is known and can be evaluated. Even if operators are given a procedure to follow, for reasons discussed in... 

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