1 CGPM 2003 CCAUV report President: Dr. Joaquín Valdés (CIPM) Executive Secretary: Dr. P. Allisy-Roberts (BIPM) CGPM 2003 CCAUV report President: Dr. Joaquín Valdés (CIPM) Executive Secretary: Dr. P. Allisy-Roberts (BIPM)

2 CCAUV first meeting July 1999 CCAUV second meeting October 2001 CCAUV third meeting October delegates, 5 observers and 1 guest CCAUV first meeting July 1999 CCAUV second meeting October 2001 CCAUV third meeting October delegates, 5 observers and 1 guest

3 CCAUV Summary of Comparison Status CCAUV Summary of Comparison Status

4 Acoustics CCAUV KeyRMO KeyRMO Suplement A-K1 PublishedAPMP K1 PlannedSIM Measurements complete A-K2 PlannedCOOMET K1 In progress A-K3 In ProgressEUROMET K1 Draft B A-K4 PlannedEUROMET K2, K3 Planned W-K1 Draft ASIM K1 Draft B SIM K1 (old) approved

5 Ultrasound CCAUV KeyRMO Key U-K1 PublishedEUROMET K1 Planned U-K2 In progressEUROMET K2 Planned

6 Vibration CCAUV KeyRMO Key V-K1 PublishedAPMP K1 Approved (linked results to be published) EUROMET K1 (old) approved EUROMET K1 In progress SIM K1 Draft A

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8 Classification of Services in AUV Document CCAUV

9 Future Needs for Metrology in AUV Report prepared by NPL (UK), PTB (Germany), IEN (Italy) and the President of CCAUV Document CCAUV

10 AUV and Nanotechnology Need to develop ever smaller transducers

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12 Achieving vibrational quantum limits with nanomembranes New standards with acoustical or thermal phonons? PHONON EMISSION ONE BY ONE

13 Schematic diagram of micromachined stereocilia mounted on a membrane, with piezoresistive strain sensors to measure deflection due to microflows (W. Tang). Array of micromachined stereocilia.

14 In the CCAUV section of the BIPM website there are documents of restricted access. Most of them will be now be open for free access. There is also an extense list of publications related to AUV.

15 The unit one, the neper and the bel The unit one, the neper and the bel

16 Logic A (current logic) –The ratio of two quantities of the same kind is a new quantity.

17 Logic B Division of one quantity by other of the same kind merely express the number of times one quantity fits into the other. This number may be just called a coefficient, a factor or a ratio, but not a new quantity. No need to assign SI units to numbers!

18 Logic A or Logic B? It is a matter of choice

19 PROBLEMS associated with Logic A CONFUSION between levels, reference levels and the underlying quantities and SI units CONFUSION through special names CONFUSION through the use of the special name decibel with different power and field quantities such as dB(mW), dB(W), dB(0.775V), dB(V), dB(mA), dB(  V/m), dB(W/m 2 ), dB(W/4kHz), dB(W/K), dB(W/m 2 kHz), dB(kHz), dB(Pa), dB(Pa/V), dB(mV/Pa) and dB(K -1 )

20 The best recommendation should be to use more the accepted SI units underlying such ratios or levels as bel or neper