Changes for page Overview

Summary

• Page properties (1 modified, 0 added, 0 removed)

Details

Page properties

Content

...	...	@@ -7,13 +7,13 @@
7	7
8	8	A tuple centre is a tuple space enhanced with the possibility to program its behaviour in response to interactions.
9	9	##
10		-First of all, coordinated entities (//#respect() agents//, henceforth, or simply //agents//) can operate on a #respect() tuple centre in the same way as on a standard Linda tuple space: by exchanging //tuples// — which are ordered collection of knowledge chunks — through a simple set of coordination primitive.
	10	+First of all, coordinated entities (//#respect() agents//, henceforth, or simply //agents//) can operate on a #respect() tuple centre in the same way as on a standard Linda tuple space: by exchanging //tuples//—which are ordered collection of knowledge chunks—through a simple set of coordination primitive.
11	11	##
12	12	So, an agent can write a tuple in a tuple centre with an #code("out") primitive; or read a tuple from a tuple centre with primitives such as #code("in"), #code("rd"), #code("inp"), #code("rdp") specifying a tuple template - that is, an identifier for a set of tuples, according to some tuple matching mechanism.
13	13	##
14	14	Reading tuples can be
15		-* //destructive// — #code("in"), #code("inp") remove the matching tuple — or //non-destructive// — #code("rd"), #code("rdp") simply read the matching tuple
16		-* //suspensive// — #code("in"), #code("rd") wait until a matching tuple is found — or //non-suspensive// — #code("inp"), #code("rdp") immediately return either the matching tuple or a failure result
	15	+* //destructive// — #code("in"), #code("inp") remove the matching tuple – or //non-destructive//– #code("rd"), #code("rdp") simply read the matching tuple
	16	+* //suspensive// — #code("in"), #code("rd") wait until a matching tuple is found – or //non-suspensive//– #code("inp"), #code("rdp") immediately return either the matching tuple or a failure result
17	17
18	18	but is anyway always //non-deterministic//: when more than one tuple in a tuple centre are found that match a tuple template, one is non-deterministically chosen among them and returned.
19	19
...	...	@@ -28,11 +28,11 @@
28	28	##
29	29	Finally, //suspensive semantics// promotes coordination patterns based on knowledge availability, and couples well with incomplete, partial knowledge.
30	30
31		-Even more, while the basic tuple centre model is independent of the type of tuple, #respect() tuple centres adopt logic tuples — both tuples and tuple templates are essentially Prolog //facts// — and logic //unification// is used as the tuple-matching mechanism.
	31	+Even more, while the basic tuple centre model is independent of the type of tuple, #respect() tuple centres adopt logic tuples – both tuples and tuple templates are essentially Prolog //facts// – and logic //unification// is used as the tuple-matching mechanism.
32	32	##
33		-So, for instance, an agent #code("ag1") performing operation #code("we ? in(activity(ag1,CaseID))") on tuple centre #code("we") containing tuples #code("activity(ag1,c16)") and #code("activity(ag2,c22)") will be returned tuple #code("activity(ag1,c16)")—the one unifying with the template — removed from #code("we").
	33	+So, for instance, an agent #code("ag1") performing operation #code("we ? in(activity(ag1,CaseID))") on tuple centre #code("we") containing tuples #code("activity(ag1,c16)") and #code("activity(ag2,c22)") will be returned tuple #code("activity(ag1,c16)")—the one unifying with the template—removed from #code("we").
34	34	##
35		-Since the overall content of a tuple centre is a multiset of logic facts, it has a twofold interpretation as either a collection of messages, or a (logic) //theory of communication// among agents — thus promoting in principle forms of //reasoning about communication//.
	35	+Since the overall content of a tuple centre is a multiset of logic facts, it has a twofold interpretation as either a collection of messages, or a (logic) //theory of communication// among agents—thus promoting in principle forms of //reasoning about communication//.
36	36
37	37	Finally, a tuple centre is a programmable tuple space, so as to add //programmability// of the coordination medium as a new dimension of coordination.
38	38	##
...	...	@@ -45,11 +45,9 @@
45	45	The original #respect() is a logic-based language for the specification of the behaviour of tuple centre.
46	46	##
47	47	As a behaviour specification language, #respect():
48		-
49		-
50	50	* enables the definition of computations within a tuple centre, called reactions, and
51	51	* makes it possible to associate reactions to events occurring in a tuple centre.
52		-<p/>
	50	+
53	53	So, #respect() has both a declarative and a procedural part.
54	54	##
55	55	As a specification language, it allows events to be declaratively associated to reactions by means of specific logic tuples, called specification tuples, whose form is #code("reaction(E,R)").
...	...	@@ -61,7 +61,7 @@
61	61	A reaction as a whole succeeds if all its reaction goals succeed, and fails otherwise.
62	62	##
63	63	Each reaction is executed sequentially with a transactional semantics: so, a failed reaction has no effect on the state of a logic tuple centre.
64		-<p/>
	62	+
65	65	All the reactions triggered by an event are executed before serving any other event: so, agents perceive the result of serving the event and executing all the associated reactions altogether as a single transition of the tuple centre state.
66	66	##
67	67	As a result, the effect of a coordination primitive on a logic tuple centre can be made as complex as needed by the coordination requirements of a system.
...	...	@@ -69,7 +69,7 @@
69	69	Generally speaking, since #respect() has been shown to be Turing-equivalent, any computable coordination law could be in principle encapsulated into a #respect() tuple centre.
70	70	##
71	71	This is why #respect() can be assumed as a general-purpose core language for coordination: a language that could then be used to represent and enact policies and rules for coordination systems of any sort.
72		-<p/>
	70	+
73	73	Adopting the declarative interpretation of logic tuples, a #respect() tuple centre has then a twofold nature a //theory of communication// (the set of the ordinary tuples) and a //theory of coordination// (the set of the specification tuples).
74	74	##
75	75	In principle, this allows intelligent agents to reason about the state of collaboration activities, and to possibly affect their dynamics.