EVOLV/wiki/Glossary.md

Glossary

Note

S88, EVOLV runtime, wastewater, pump / hydraulics, control, and project terms. Use this page as a dictionary while reading the other wiki pages.

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S88 — ISA-88 batch control

flowchart TB
    enterprise["Enterprise"]
    site["Site"]
    area["Area"]
    pc["Process Cell"]
    unit["Unit"]
    em["Equipment Module"]
    cm["Control Module"]

    enterprise --> site --> area --> pc --> unit --> em --> cm

    class enterprise,site neutral
    class area area
    class pc pc
    class unit unit
    class em equip
    class cm ctrl

    classDef neutral fill:#dddddd
    classDef area fill:#0f52a5,color:#fff
    classDef pc fill:#0c99d9,color:#fff
    classDef unit fill:#50a8d9,color:#000
    classDef equip fill:#86bbdd,color:#000
    classDef ctrl fill:#a9daee,color:#000

Term	Meaning in EVOLV
Area	Plant section. Reserved — no node implements it yet
Process Cell (PC)	Self-contained sub-process. pumpingStation is the only PC-level node
Unit (UN)	One major piece of equipment or a coordinator. MGC, VGC, reactor, settler, monster
Equipment Module (EM)	A single piece of equipment. rotatingMachine, valve, diffuser
Control Module (CM)	A single sensor or actuator. measurement
softwareType	The node's S88 type. Used by ChildRouter to match child.register

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EVOLV runtime

Term	Meaning
BaseDomain	Base class for every specificClass. Owns measurements, router, emitter, logger
BaseNodeAdapter	Base class for every nodeClass. Bridges Node-RED to specificClass via commandRegistry
specificClass	Pure-JS domain logic. No RED.* imports. Unit-testable in isolation
nodeClass	Node-RED adapter — input routing, tick loop, port wiring, status badge
ChildRouter	Declarative matcher for child.register. router.onRegister(swType, handler)
commandRegistry	Inbound-msg dispatcher. Topic to descriptor; resolves aliases, coerces units
UnitPolicy	Per-node declaration of canonical (internal) and output units
MeasurementContainer	Chainable measurement store. Keys: <type>.<variant>.<position>.<childId>
statusBadge	Composes node.status({fill, shape, text}) from a HealthStatus
HealthStatus	{level: 0..3, flags, message, source} — standardised health summary
LatestWinsGate	Mutex with supersede semantics. Superseded calls resolve with {superseded: true}
outputUtils	Port-0 delta compression and Port-1 line-protocol formatting
tick	1 Hz update loop. Opt-in via static tickInterval = N on nodeClass
'output-changed'	Event the specificClass fires on this.emitter when public state shifts
getOutput()	Domain method returning the current snapshot — fed to outputUtils
getFlattenedOutput()	Measurements with dot-flattened keys (4-segment type.variant.position.childId)

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Topic prefixes

See Topic Conventions for the full reference.

Prefix	Direction	Idempotent
set.	in	Yes
cmd.	in	No (side-effects)
data.	in / out	n/a
query.	in	Yes (read-only)
child.	in (parent)	Yes (id-keyed)
evt.	out	n/a

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Wastewater treatment terms

Term	Meaning
WWTP	Wastewater Treatment Plant
Influent / Effluent	Inlet / outlet stream of a process unit
Activated Sludge	Biological process — bacteria consume organic matter under aeration. Modelled by ASM1, ASM3
MLSS	Mixed Liquor Suspended Solids — biomass concentration in the reactor
RAS	Return Activated Sludge — settled sludge pumped back from settler to reactor
WAS	Waste Activated Sludge — excess sludge removed from the system
TSS	Total Suspended Solids
COD / BOD	Chemical / Biological Oxygen Demand — organic load metrics
NH4 / NO3	Ammonium / Nitrate — N species, key for nitrification / denitrification
DO	Dissolved Oxygen (mg/L). Setpoint typically around 2 mg/L in aerated zones
K_La	Volumetric mass-transfer coefficient (oxygen transfer rate / driving force)
OTR	Oxygen Transfer Rate — diffuser's output to the reactor
HRT / SRT	Hydraulic / Sludge Retention Time
F/M ratio	Food-to-microorganism ratio
Composite sample	A sample built over time, often flow-proportional — what monster simulates

See ASM Models for biological kinetics in detail.

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Pump / hydraulics terms

Term	Meaning
BEP	Best Efficiency Point — operating point with minimum energy per unit flow
NPSH	Net Positive Suction Head — pressure margin to avoid cavitation
Affinity laws	Q proportional N, H proportional N-squared, P proportional N-cubed — how flow / head / power scale with pump speed
Characteristic curve	Q to H (or Q to P, Q to efficiency) graph supplied by the pump manufacturer
NCog	Normalised cost-of-going metric used by MGC for switching stability
Wet-well basin	Buffer volume on a lift station — what pumpingStation models
Setpoint	Commanded value (e.g. flow setpoint = 12 m3/h)
Demand	Integrated requirement (e.g. parent's "need this much flow now")

See Pump Affinity Laws and BEP Gravitation Proof.

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Control / signal-processing terms

Term	Meaning
PID	Proportional-Integral-Derivative controller
Anti-windup	Prevents the integral term from growing unboundedly when the actuator saturates
Hysteresis	Switching threshold with a deadband (e.g. start at 80%, stop at 30%)
Schmitt trigger	Hysteresis-based binary switch (used for stopLevel in pumpingStation)
Smoothing	Filtering noise (moving average, exponential, Savitzky-Golay)
Outlier detection	Identifying readings outside expected variance
FSM	Finite State Machine — discrete states + transitions

See PID Control Theory and Signal Processing — Sensors.

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Project terms

Term	Meaning
Tier 1–4	Refactor phases. See Home Refactor status
Wave A / B / C	Sub-batches of submodule pointer bumps during the refactor
OPEN_QUESTIONS.md	Live decisions log at .claude/refactor/OPEN_QUESTIONS.md
CONTRACTS.md	API shapes at .claude/refactor/CONTRACTS.md
MODULE_SPLIT.md	Per-node concern layout at .claude/refactor/MODULE_SPLIT.md
CONVENTIONS.md	Code style and naming at .claude/refactor/CONVENTIONS.md
WIKI_TEMPLATE.md	Per-node 14-section template at .claude/refactor/WIKI_TEMPLATE.md
AUTOGEN block	Sections regenerated by npm run wiki:all. Do not hand-edit between markers

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Related pages

Page	Why
Home	Top-level node map
Architecture	Runtime concepts in context
Topic Conventions	Full topic / unit / colour reference
Topology Patterns	Terms used in plant scenarios