H17 — Portability
TUNES is London-first, not London-hardcoded. The core model describes generic railway topology, journeys, sections, observations, measurements and provenance; each network supplies versioned configuration.
For: maintainers adding networks, researchers comparing cities, and recorder/map implementers.
Assumptions: expansion follows validation and local governance; schema portability does not imply launch coverage, data availability, operator participation, or endorsement.
Core model versus configuration
| Core schema | Network or deployment configuration |
|---|---|
| Transport system, operator, line, branch, direction | Local names, identifiers, language and passenger-facing direction labels |
| Station, optional platform, directed section | Topology, interchange edges, branches, stopping patterns and geometries |
| Journey, section, timeline segment and duration | Route-selection rules and alignment priors |
| Rolling stock and carriage-position concepts | Local stock catalogue and passenger-friendly carriage labels |
| Measurements, calibration, flags, confidence | Supported device profiles, campaign protocols and quality gates |
| Versioned observation and release provenance | Data-source licences, network-profile version and release scope |
| Objective/subjective separation | Localised survey wording and accessibility review |
Configuration must not redefine acoustic quantities or weaken claim, privacy, consent, or reproducibility rules.
flowchart TD
C[Generic TUNES core]
C --> L[London profile]
C --> P[Paris profile]
C --> T[Tokyo profile]
C --> N[New York profile]
L --> O1[Versioned local topology and labels]
P --> O2[Versioned local topology and labels]
T --> O3[Versioned local topology and labels]
N --> O4[Versioned local topology and labels]
Network application
| Network | What remains unchanged | What becomes configuration |
|---|---|---|
| London Underground | Directed station-to-station sections, duration, observation and quality model | London profile, line/branch topology, local direction labels, stock and map geometry |
| National Rail | Same section and measurement contracts | Operator/service instances, stopping patterns, shared stations, route and stock data |
| Paris Metro | Same generic entities and provenance | Local systems, lines, station identifiers, labels, topology and licences |
| Tokyo Metro | Same objective/subjective separation and release versioning | Local systems/operators, multilingual labels, service patterns, topology and licences |
| NYC Subway | Same journey, directed section and confidence model | Local routes/services, direction labels, stopping patterns, branches and licences |
These rows state how a profile would be represented. They do not claim that profiles, imports, partnerships, or validated collectors for Paris, Tokyo, or New York already exist.
Why the core does not change
- A city adds instance rows and a versioned network profile, not city-specific entity classes.
- Direction uses stable IDs plus local labels; it is not limited to “eastbound/westbound”.
- Branches and optional service/trip entities represent divergent and stopping-pattern complexity.
- Shared stations and multiple operators are relationships, not schema exceptions.
- Section identity is stable within a network-profile version and remains interpretable with old releases.
- Local map geometry changes presentation, not measurement meaning.
Portability also has scientific limits. Different stock, tunnels, weather exposure, operating practices, device populations, languages, and passenger expectations affect observations. Cross-city comparison therefore requires compatible protocols and uncertainty analysis; schema compatibility alone is not scientific comparability.
Addition checklist
- Define scope and ownership; preserve non-affiliation language.
- Confirm source licences before importing topology or operational data.
- Create a versioned network profile with stable opaque IDs and localised labels.
- Validate legal paths through topology, branches, directions and stopping patterns.
- Test route selection, offline recording, alignment and correction in the local network.
- Characterise devices, stock and environmental conditions; do not inherit London accuracy assumptions.
- Publish profile, schema, pipeline, limitations and release IDs together.
Future work
Only a minimal London Underground profile stub exists in
v0.1.0. Full London, National Rail, Paris, Tokyo and New York profiles; localisation contracts; service-pattern rules; and cross-city comparability protocols are not yet defined.
Related Documents
What is TUNES · Repos · Schema · Assumptions · Railway journey model · Generic schema ADR · Initial network scope ADR · Network-profile schema