...Nikos Germenis; Georgios Dimitrakakis; Efthimios Sokos; Pantelis Nikolakopoulos Abstract A new class‐A force‐balance accelerometer (FBA) is designed, simulated, and evaluated. The focus of this work was to design a low‐cost but high‐performance instrument. The FBA has output voltage proportional...

... structure for comparison. REF TEK force balance triaxial borehole accelerometers form the downhole array to capture the propagation and travel time from the lowest downhole depth to the ground surface. Large and abrupt changes may indicate damage to structural components, allowing engineers to rapidly...

... communication, real‐time auxiliary and state‐of‐health (SOH) channels, event processing and triggers, remote firmware upgrades, and features for earthquake early warning, such as low data latency. Mandatory criteria for the triaxial, broadband, force‐balance accelerometers were full‐scale range of ± 4...

... and employed in this study as the reference sensor, the EpiSensor is a triaxial force-balance servo accelerometer optimized for earthquake recording applications. A widely used accelerometer, the EpiSensor consists of three orthogonally co-mounted force-balance sensors per axis. The EpiSensor, FBA ES-T, has...

... and crosses the Denali fault perpendicularly about 87 km east of the epicenter (Figure 1). The Alyeska pump-station records and the instrumental characteristics were provided to the USGS by Alyeska under a cooperative agreement. The pump stations are equipped with Honeywell Sundstrand force-balance...

...) . Since 2011, the network has been further developed, and it now consists of 43 broadband and short‐ and mean‐period stations, 83 strong‐motion stations (29 force balance accelerometers collocated with seismometers and 54 micro electro‐mechanical systems [MEMS]–based accelerometers installed at selected...

... distributed on 10 levels (Fig.  4 ): basement, 1st (ground), 2nd, 7th, 8th, 13th, 14th, 19th, 20th, and roof. Among the sensors, 29 of them are 2 g ‐uniaxial (Kinemetrics ES‐U) and one triaxial Force Balance Accelerometers (Kinemetrics ES‐T) with 1.25    V / g sensitivity. The ES‐T (channels 1...

..., and located in the Po plain, were assigned to class C and denoted with a dagger. The strong‐motion stations are equipped with Kinemetrics Episensor or Syscom MS2007+, which are triaxial force balance sensors, with a natural frequency above 50 Hz set to or full‐scale. They are coupled...

... transformer models supporting a bushing, are presented. Experimental results are consistent with the analytical results and further support the effectiveness of FPS bearings in reducing inertia forces, thus, providing a suitable procedure to mitigate the seismic hazard of substation transformers. © 2001...

... Program (TSMIP), which has recorded the strong ground motions at free field since 1992. The details regarding the network can be found in Liu et al. (1999) . Each station is equipped with triaxial force‐balanced accelerometers, with a flat frequency response from direct current to about 50.0 Hz...

... accelerometer of Block and Moore (1970) was constructed to illustrate this principle. Feedback is used in many other situations where, although it results in improved linearity and broader band response, it does not lower noise levels. The use of electromagnetic feedback, which allows large feedback forces...

... Kinemetrics K2 digital recorders near the mainshock epicenter between 12 and 28 February 2001. Each K2 included an internal triaxial force-balance accelerometer set to full scale of 2 g and a built-in GPS timing system. An external velocity sensor (Mark Products triaxial L-28) was also attached to each K2...

...-channel re- The SMART1 seismic array was installed in the corders. The pre-event memory is set to 10 sec. Ground northeast corner of Taiwan (Fig. 2). It is a dense array motions are digitized at 200 samples per second, so that of 39 force-balanced triaxial accelerometers configured the Nyquist frequency...

... triaxial force balance accelerometers and GSR‐18 strong‐motion recorders with GSD 18‐bit digitizer. Average interstation distance is 20–30 km in the hilly regions and 40–50 km in the plains ( Kumar et al. , 2012 ). The accelerograms recorded by this network are accessible from the PESMOS website (see...

...-precision geophysical measurements. These inherently digital sensors operate in the time domain with orders of magnitude improved performance compared to traditional analog transducers. Quartz crystal absolute pressure gauges, triaxial accelerometers and rotation sensors measure short-term events like...

... and certified the treasurer’s report. The fiscal year is 1 September to 31 August. The checking account balance is relatively high to pay for digitizing older issues of SRL and Earthquake Notes . Dues increased this last year and will increase...

...), useful resolution (NU), collocated recording comparison and shake map generation. The results proved that GL-P2B can be classified as a type of Class-B sensor. The records obtained are consistent with the data obtained by the collocated traditional force-balanced accelerometers even for stations...

.... In this contribution, we report on the progress towards EEW readiness throughout the project to date. Optimizing EEW systems have led to demon- strate the possible speed and quality of earthquake parameter estimations. 70 EEW-ready class A force balance accelerographs are being installed across the region to reduce...

... with today’s and future challenges. Engaging this new blood in any organization, with the right balance of freedom and guidance, maximizes the utilization of such force and keep the motivation at high levels. Bérengère Savary-Sismondini (Schlumberger, Norway < bsavary@stavanger.oilfield.slb.com...