Some Aspects of Propagation

Operators Are Not Functions

Network operators rarely behave as functions -

• they can have multiple outputs• a range can turn into a domain• some operator pairs cooperate• topology is altered• direction is locally determined• they can destroy themselves

Multiple Simultaneous Outputs

ANDAND

The SPINE operator behaves as an AND, so setting an environment can communicate a state to thousands of statements

Range to Domain

ABS-55

ABS-5,55

Some operators reverse the operation of functions

Turning It Around

+

Some operators receive a message, and immediately send a consistent reduced message back along the same path

Operator CooperationSome operator pairs cooperate strongly -

• FOR/GETPUT• ACTIVITY/RESOURCE• DISTRIB/RELATION

Some of these use spreading activation rather than message passing

X=5 = + ListLink =

B=9

C=3A%

D

A%ListLink

Altering Connections

The LISTLINK operator alters the topology of the network

X = +

B

C

D

B=9

C=3X=5

D=-7

+

Flow on Connection

The LISTLINK detaches itself and links the variables directly to the PLUS, at which point information flows in whichever direction the arrows indicate

ListLink A%A%ListLink

Creative Destruction

Operators can represent objects, which are created and destroyed

Phasing of operations in a network can be a considerable problem, because of the network’s unpredictable transmission delays.

This problem is exacerbated when a single processor is emulating a network of autonomous cells or agents.

One way around this is to add connections - to change the topology.

Alternative Tags

The initial tag values arrive at the operator - there are two alternatives on the right hand side

PARSEArticleNoun/Verb

“The” “quake”

Alternative Tags

The verb tag alternative is pruned, as the verb could not be preceded by an article. There is now a possibility to detect a noun phrase, which requires that all the nodes to be checked have singular values. But how long before the new value reaches the node?

PARSEArticleNoun/Verb

“The” “quake”

Alternative Tags

Forming a new connection to the node at the same time as propagating the value in the link guarantees the value has reached the node before the operator triggers the search for a noun phrase.

PARSEArticleNoun/Verb

“The” “quake”

Alternative Tags

The state from the node triggers the operator to search for a noun phrase.

PARSEArticleNoun/Verb

“The” “quake”

Throwing a ConnectionInstead of using a timer, we can create a

connection to tell us exactly when we can restart

Problem: We have been prompted to search, but one connection is not ready - how do we restart when it is readySolution: Make a connection, wait for the change of state to tell us it is ready - use the connection paradigm and extend it

Back Connections

Forming back-connections is a powerful way of phasing operations in a network - whether in a computer or in a person’s head

Why a Structure?

The activity in the structure, and its continual self-modification, would make the life of any outside algorithm very difficult

IF A > 5 THEN BEGIN ........... IF B = 3 THEN BEGIN ........... PROC_C ...........