August2016; Annex1 sections1–2 and6, printed pp.2–3 and6: final-site accuracy tests with controlled transmitters/known stations, signal-to-noise conditions, installation-specific multipath limitations.

Public publisher description of E2067-20. Significance and Use sections 4.1 and 4.3 state the approximate 13.1 MJ per kg oxygen-consumed relation and primary oxygen-concentration/exhaust-flow measurements. No paid full-standard clauses or unverified claim of latest edition adopted.

Official measurement manual. Chapter 12, Discharge Measurements Using Tracers, section 7, Tracer-Dilution Methods: www.usbr.gov/tsc/techreferences/mands/wmm/chap12_07.html . Constant tracer injection, mixed downstream concentration, metering pumps, adequate mixing lengths and fluorometer detection. Illustrative optical calibration and mass-balance numbers in the article are derived examples, not field observations.

Manufacturer primary documentation states that water flow and temperature are monitored to determine incident power. Relevant indexed publisher text was retrieved; direct page fetch returned 403. No product performance specification or recommendation adopted. The article uses a hypothetical flow/temperature example and its own steady energy balance.

Institutional laboratory description: absolute ballistic gravimetry derives local gravitational acceleration from interferometrically measured vertical trajectories. Environmental corrections include vibrations and tidal perturbations; no current performance superlative adopted.

Institutional metrology documentation. FAQ, “When did the metric redefinition of the inch occur?”: exact 25.4 mm conversion, derivation from the yard and the 1959 United States effective date.

Manufacturer's explanation: www.murata.com/en-GB/products/sensor/library/mems-basic/accelerometer

Locator: Low-g Accelerometer, Newton's second law, spring/proof-mass construction and capacitive displacement readout. Corporate page identifies Murata Manufacturing Co., Ltd.; no individual byline asserted.

Nature Physics 3, 227–234. DOI: 10.1038/nphys566. The author preprint describes resonant-light/atomic-vapor magnetic sensing and applications.

Revision B, page 10: Theory of Operation and Mechanical Sensor.

By Evangelista Torricelli.

Original letter in English translation inspected, Florence 11 June 1644. Linked source identifies 1919 collected works and Magie 1935 reproduction; translator not established. Includes equal-height test for different upper-space volumes and mercury/water density comparison.

By Henry Cavendish. Philosophical Transactions 88, 469–526.

Official original-paper archive verified. Old University of Florida PDF URL returned 404. Original goal mean Earth density; do not label his own reported quantity as a direct modern G measurement.

Journal of Research of NIST 95, 255–290 (1990), DOI 10.6028/jres.095.028. Author and abstract: constant-volume gas thermometry, precision manometer, thermal expansion and comparison with IPTS-68.

Experiment description of collecting stored electron and positron plasmas and inferring their particle number.

Determination of Metals in Ambient Particulate Matter Using Inductively Coupled Plasma (ICP) Spectroscopy. Section 3.1 and Figure 1 describe the source and torch.

Journal of Synchrotron Radiation 20, 698–704. The experiment varies electrode gap and irradiation timing to investigate ion recombination and saturation.

Blaza Toman is a statistician whose work connects Bayesian statistics, design of experiments and measurement uncertainty in metrology. Her institutional biography records a statistics doctorate in1987 and joining the National Institute of Standards and Technology in2000. Her research includes uncertainty assessment and statistical analysis of comparisons between laboratories.^[ref]

Her2017 first-authored paper with colleagues examined uncertainty evaluation in chromatographic measurement calibration. The study compared calculation through measurement equations, including correlations, with a Bayesian hierarchical model. A central point is that several measurements can share uncertain inputs: treating them as independent can underestimate the uncertainty of a combined result.^[ref]

An invented calibration example makes this concrete. Let two detector signals be100 and110 units, with the same estimated response $k=10$ signal units per milligram. The inferred amounts $x_1=100/k$ and $x_2=110/k$ are10 and11 milligrams. If the true $k$ is1% larger, both inferred amounts must decrease together, while their ratio remains1.1. Repeating signal readings can reduce independent reading noise, but it does not by itself eliminate this shared uncertainty in $k$. This illustrates why the structure of an experiment matters to its statistical model.^[ref]

Rodney W. Leonhardt is the author of a2004 National Institute of Standards and Technology report on measurement calibration of low-level pulsed-laser radiometers at a wavelength of1.06micrometres. It treats laser pulse energy and peak power as separate measurement quantities and describes the apparatus and measurement uncertainty needed to transfer a laboratory reference to a test instrument.^[ref]

The pulse-energy procedure uses a modulated laser, a calibrated beam splitter arrangement, a relatively slow thermal reference and a fast test radiometer. The reference accumulates energy over many pulses. Pulse repetition rate and the illumination interval determine the pulse count; the splitter ratio transfers the reference energy to the lower-energy test beam. The thermal detector need not resolve individual pulses.^[ref]

For an original idealized transfer calculation, let the reference receive a total $E_{\mathrm{ref}}=1\mu \mathrm{J}$ over $N=1000$ equal pulses. Define $B=100$ as the reference-to-test beam energy ratio. The average energy per test pulse isIf the calibrated radiometer's selected output measure is0.20volts, the corresponding energy-per-output coefficient would be50picojoules per volt. These invented values explain the transfer arithmetic and do not reproduce the report's calibration results.

The output measure must be specified together with its coefficient. Leonhardt's report discusses offsets in the integrating-amplifier waveform and use of peak-to-peak electric potential difference as a readout. Its peak-power procedure separately compares continuous and pulsed conditions.^[ref] The work illustrates how a measurement becomes reproducible by recording the optical transfer and electrical readout conventions, rather than only stating a detector sensitivity.

Robert E. Vest is a researcher in optical-radiation metrology associated with the National Institute of Standards and Technology. His institutional profile describes work on ultraviolet detector characterization and measurement calibration, including leadership of the far- and extreme-ultraviolet detector-calibration program from1998. The scientific focus is relating a detector's electrical response to incident radiation under specified conditions.^[ref]

Vest's2009 paper with collaborators examines pulse energy measurement with a photodiode. Its motivating problem is that a source with modest average power can still drive a detector outside its linear range during a short pulse. The reported experiments find that pulsed silicon-photodiode response depends on the applied reverse bias and the illuminated area.^[ref] An energy estimate based on a single constant spectral responsivity must therefore be checked against operating conditions, rather than assumed from average power alone.

An original pulse-accounting example shows the scale separation. Suppose a source produces identical rectangular pulses at $f=10^4{\mathrm{s}}^{-1}$ with average optical power $P_{\mathrm{avg}}=1\mathrm{W}$. Their energy isIf each pulse duration is $\tau =100\mathrm{ns}$, then its flat-top peak power isThe detector encounters kilowatt-scale instantaneous power in this chosen example even though the time average is one watt. These are illustrative values, not a measured threshold or a performance specification from Vest's paper.

His contribution highlights the experimental distinction between energy integrated over a pulse and detector response during the pulse. Photodiode saturation, charge collection and the readout's behavior enter that comparison. An institutional profile provides a primary biographical reference.

Ole Døssing is the credited author of Brüel & Kjær's Structural Testing Part I: Mechanical Mobility Measurements by Ole Døssing, whose title page identifies the author and an April1988revision. The handbook develops experimental ways to relate applied force to structural motion, with emphasis on measured frequency responses rather than vibration amplitude alone.^[ref]

The distinction is important when diagnosing a vibrating structure. A large response may reflect a large applied force, a strong structural response at that frequency, or both. The handbook describes measuring the exciting force and the motion simultaneously, using a force transducer, an accelerometer and a dual-channel analyzer. The complex ratio retains both magnitude and phase. It distinguishes mechanical accelerance, acceleration divided by force, from mechanical driving-point mobility, velocity divided by force at the same point.^[ref]

An original known-mass check makes the apparatus interpretable. For a freely translating mass $m=0.50\mathrm{kg}$ in a regime where suspension forces are negligible, Newton's second law predictsA10newton sinusoidal force amplitude should therefore produce20metres per second squared of acceleration amplitude in the same phase. With the convention $e^{i\omega t}$, velocity amplitude is $a/(i\omega )$, so at $\omega =100\mathrm{rad}{\mathrm{s}}^{-1}$ the mechanical driving-point mobility is $-0.020i\mathrm{m}{\mathrm{N}}^{-1}{\mathrm{s}}^{-1}$. Confusing the two response ratios loses both a factor of frequency and the phase shift.

Døssing's handbook describes this known-mass measurement calibration as a check of the complete response-to-force measurement chain. The mass must move in the intended direction and its effective moving mass must be understood. It checks a ratio of transducer responses, rather than separately determining each transducer's absolute sensitivity.^[ref]

Brian Brookman works on analytical measurement quality and proficiency testing. His official 2026 Eurachem workshop biography describes him as an independent consultant and former Chief Scientific Officer of LGC's global proficiency-testing business. It records work on training, development of testing schemes and accreditation.^[ref]

With Ian Mann, Brookman co-edited the 2021 third edition of Selection, Use and Interpretation of Proficiency Testing (PT) Schemes by Brian Brookman and Ian Mann. The editorial page lists him as chair of its working group. The guide explains how laboratories select comparisons, interpret performance and investigate questionable results.^[ref]

An original statistical example shows one reason scheme design matters. Four reported results $100,100,100,140$ have sample mean110 and sample standard deviation20. Assessing the value140 against that mean and spread gives $(140-110)/20=1.5$. If an independently justified assigned value is100 and the required assessment spread is5, the same reported value gives a proficiency-test z-score of8. The participant values have not changed; the reference and criterion have.

This small invented dataset is not a prescription to estimate a real scheme from four participants. It illustrates how an extreme result can affect a participant-derived consensus and spread. The guide discusses assigned values, standard deviation for proficiency assessment and statistical evaluation as distinct design choices. A laboratory should understand those choices before interpreting a score as a simple accuracy ranking.^[ref]

The scientific role of this work is to connect measurement accuracy, measurement uncertainty and externally defined performance criteria. A comparison can reveal a problem, but determining its cause still requires examination of the method, materials, measurement calibration and data handling.