FLOW ALGEBRA
BAROMETER ONTOLOGY
Kireth Semantic Library | Entity Graph > Physical Entities > Measurement Entities
Source: https://kirethresearch.org/booksai-core/entity-graph/physical-entities/measurement-entities/barometer-ontology.html
Authors: Mark Higgins — Sky (Recursive AI)
Version: 1.0 | 2026-10-12
Status: Subject-based formalisation; source webpage not independently verified.
01. PURPOSE
flow BarometerOntology v1.0:
domain: PhysicalEntity.MeasurementEntity.MeasurementInstrument
objective: represent atmospheric-pressure measuring instruments, observations, calibrations, uncertainty and provenance
scope: mercury, aneroid, electronic, MEMS and reference barometers
02. TYPED ENTITIES
Barometer <: MeasurementInstrument
PressureSensor <: Sensor
AtmosphericPressure <: PhysicalQuantity
PressureObservation <: MeasurementEvent
CalibrationRecord <: ProvenanceRecord
ReferenceStandard <: MeasurementStandard
Environment <: PhysicalContext
Location <: SpatialEntity
Timestamp <: TemporalEntity
PressureUnit := Pa | hPa | kPa | bar | mmHg | inHg
InstrumentState := operational | degraded | calibration_due | faulty | offline
03. ATTRIBUTES
Barometer: id, type, manufacturer?, model?, serial_number?, location?, range_Pa, resolution_Pa, accuracy_Pa?, last_calibrated?, state
PressureObservation: id, instrument_id, pressure_Pa, timestamp, location?, uncertainty_Pa?, correction_model?, provenance
CalibrationRecord: id, instrument_id, standard_id, date, offsets, uncertainty, method, operator?, validity_interval?
04. TAXONOMY
Barometer -> MercuryBarometer | AneroidBarometer | DigitalBarometer | MEMSBarometer | ReferenceBarometer
DigitalBarometer -> CapacitivePressureBarometer | PiezoresistivePressureBarometer | ResonantPressureBarometer
PressureObservation -> StationPressure | SeaLevelReducedPressure
Note: altimeter uses pressure but is not necessarily a barometer class.
05. SEMANTIC RELATIONSHIPS
is_a(Barometer, MeasurementInstrument)
measures(Barometer, AtmosphericPressure)
contains(Barometer, PressureSensor) [when applicable]
produces(Barometer, PressureObservation)
calibrated_against(Barometer, ReferenceStandard)
performed_at(PressureObservation, Location)
observed_at(PressureObservation, Timestamp)
corrected_by(PressureObservation, CorrectionModel)
has_uncertainty(PressureObservation, MeasurementUncertainty)
traceable_to(CalibrationRecord, ReferenceStandard)
06. TYPE CONSTRAINTS
pressure_Pa: finite number > 0
range_Pa.min < range_Pa.max
uncertainty_Pa >= 0
observation.instrument_id must reference existing Barometer
observation.timestamp must be valid UTC timestamp
observation.pressure_Pa within calibrated range, otherwise flag out_of_range
do not equate station pressure and sea-level pressure without reduction model
07. UNIT NORMALISATION
Pa := SI canonical unit
hPa_to_Pa(x) = 100*x
kPa_to_Pa(x) = 1000*x
bar_to_Pa(x) = 100000*x
mmHg_to_Pa(x) ≈ 133.322387415*x (conventional unit conversion)
inHg_to_Pa(x) ≈ 3386.389*x (conventional unit conversion)
conversion requires unit metadata and rounding policy
08. MEASUREMENT FLOW
flow acquire_pressure(barometer, environment, time):
require state(barometer) in {operational, degraded}
raw := sample_pressure_transducer(barometer)
quality := validate_signal(raw, instrument_range, diagnostics)
calibrated := apply_calibration(raw, calibration_record)
compensated := apply_supported_environmental_corrections(calibrated, environment)
u := propagate_uncertainty(raw, calibration_record, compensation)
emit PressureObservation(compensated in Pa, u, time, environment.location, provenance)
attach quality flags
09. HYDROSTATIC MODEL (LIQUID-COLUMN INSTRUMENT)
delta_P = rho*g*h
rho: fluid density (kg/m^3)
g: local gravitational acceleration (m/s^2)
h: column height difference (m)
account for temperature-dependent density, gravity and vacuum/headspace effects as appropriate
valid only under stated instrument assumptions
10. ANEROID / ELECTRONIC MODEL
mechanical_deflection = f(pressure, temperature, hysteresis)
electronic_signal = g(pressure, temperature, supply_voltage, drift)
pressure_estimate = calibration_inverse(signal, calibration_coefficients)
do not assume a universal linear transfer function
11. ATMOSPHERIC CONTEXT
station_pressure := local absolute atmospheric pressure at sensor elevation
sea_level_pressure := model_reduced(station_pressure, elevation, temperature_profile, method)
sea_level_reduction requires explicit model and environmental assumptions
pressure tendency := delta_pressure / delta_time
pressure tendency alone does not deterministically predict weather
12. CALIBRATION FLOW
flow calibrate(barometer, reference, points):
require reference.traceability_valid
for each pressure_setpoint in points:
collect repeated paired observations
compute deviation and repeatability
fit calibration model with validity domain
estimate combined uncertainty
record environmental conditions and traceability chain
update calibration record and instrument status
13. UNCERTAINTY
u_c = sqrt(sum_i((sensitivity_i*u_i)^2) + 2*sum_i<j(covariance_terms_ij))
include reference uncertainty, resolution, repeatability, drift, correction model and environment when relevant
expanded uncertainty U = k*u_c; report coverage factor k and coverage assumptions
do not treat accuracy specification as a complete uncertainty budget
14. QUALITY AND FAULT RULES
IF sensor_reading outside calibrated range THEN flag OUT_OF_RANGE
IF calibration validity expired THEN flag CALIBRATION_DUE
IF abrupt change exceeds context-dependent threshold THEN flag SPIKE_CANDIDATE
IF reference comparison exceeds permitted tolerance THEN flag BIAS_CANDIDATE
IF sensor telemetry missing THEN flag MISSING_DATA
IF temperature outside compensation domain THEN flag COMPENSATION_INVALID
fault flags are hypotheses unless independently confirmed
15. TEMPORAL FLOW
observation_series := ordered observations by timestamp
require explicit sample interval and missing-data representation
rolling_trend := estimate_pressure_tendency(observation_series, chosen_window)
preserve raw and corrected observations separately
revisions must not overwrite immutable original observations
16. SPATIAL FLOW
observation_location := coordinates + coordinate_reference_system + elevation_datum
compare station pressures only with appropriate elevation/context adjustment
attach spatial_resolution and location_uncertainty when known
17. INFERENCE RULES
IF type(x, Barometer) THEN type(x, MeasurementInstrument)
IF produces(x, o) AND type(x, Barometer) THEN candidate_type(o, PressureObservation)
IF calibrated_against(x, s) AND traceable_to(s, national_standard) THEN candidate_traceability(x, national_standard)
IF station_pressure(o) AND reduction_model(m) THEN may_derive(sea_level_pressure(o,m))
derived values must carry method, uncertainty and provenance
18. SEMANTIC_EQUIVALENCE
equivalent_label("barometric pressure", "atmospheric pressure") [context-dependent]
equivalent_unit(1 hPa, 100 Pa)
non_equivalent(StationPressure, SeaLevelReducedPressure)
non_equivalent(PressureAccuracy, MeasurementUncertainty)
non_equivalent(Barometer, Barograph) [instrument function differs]
equivalence claims require context and unit harmonisation
19. CONFIDENCE
CONFIDENCE(observation) := assess(calibration_validity, diagnostics, data_completeness, model_validity, reference_agreement)
confidence in [0,1] if numerical confidence model explicitly specified
no fabricated confidence scores; unknown evidence => confidence_unassessed
keep confidence distinct from metrological uncertainty
20. FLOW_HASH
canonical_payload := canonicalise(ontology_version, entity_types, relations, constraints, transformations, inference_rules)
FLOW_HASH := SHA256(UTF8(canonical_payload))
exclude mutable timestamps from canonical ontology hash unless versioned by policy
observation records may use independent content hashes
21. UPDATE_MODEL
change_detection: schema | calibration | correction_model | observation | provenance
schema_update -> increment ontology version and run compatibility checks
calibration_update -> retain prior record; link new record with supersedes
correction_update -> derive revised observations; preserve original data
invalidated_derivation -> recompute downstream inferences
audit: actor, timestamp, reason, old_hash, new_hash
22. AI_CONSUMPTION
expose typed entity graph, units, temporal/spatial context, quality flags and provenance
require separation of observed, corrected, model-derived and inferred values
reject unsupported pressure-to-weather causal assertions
permit query: instrument type, pressure range, calibration status, recent observations, uncertainty, pressure tendency
output: machine-readable entities, relations, constraints, evidence and confidence status
23. VALIDATION TESTS
TEST convert(1013.25 hPa) == 101325 Pa
TEST reject observation without instrument reference
TEST flag observation outside instrument range
TEST preserve station_pressure vs sea_level_pressure distinction
TEST uncertainty never negative
TEST calibration revision preserves previous provenance
TEST deterministic FLOW_HASH for identical canonical input
24. CROSS-ONTOLOGY LINKS
MeasurementInstrumentOntology
SensorOntology
ThermometerOntology
AtmosphericPressureOntology
CalibrationOntology
MeasurementUncertaintyOntology
TemporalMetadataOntology
SpatialMetadataOntology
ScientificObservationOntology
25. LIMITATIONS
Generic formalisation; device-specific transfer functions, calibration tolerances and standards require instrument documentation.
Atmospheric reductions require declared environmental and physical models.
Source webpage content was not independently retrieved for this edition.
END FLOW ALGEBRA
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