dispatcher is “selling” orders to drivers inspiring
them to provide better service.
Described interaction can be technically
organized with modern info communicational
technologies. In order to automate the solution when
driver requirements are known preliminary a
negotiation process can be simulated in the virtual
environment organized in the form of P2P network
of software agents that represent decision-makers.
Resource distribution in the described environment
can be organized on the basis of auction model.
According to this model the order can be treated as a
lot, dispatcher as an auctioneer and drivers as
bidders. The strategic aim of this auction is to
maximize the load of resources that increases the
risks of fail to serve the order and make the whole
schedule inconsistent.
Auction can be defined as a public sell of one lot
according to the predefined rules. The auctioneer or
the Centre (the agent that represents a centralized
dispatcher) at different moments of time exposes lots
(orders), which are of different level of interest to
the bidders (drivers or their agents). The winner of
the auction is an agent who buys a lot according to
the rules. The aim of an agent is to win as much lots
as possible that are of a particular interest for him at
minimal prices.
The proposed auction is divided into an uncertain
number of iterations. Blind bids are made during the
iterations, and the Centre announces the highest bid
afterwards. The Centre announces the price for new
iteration and the approximate duration of the
following iteration. In response any of the
participants can increase the bid and thus initiate a
new iteration. Auction is finished when no new bids
are made during the iteration.
In real auction auctioneer makes pauses between
gavel heats to stimulate making higher bids faster.
The same way in multi-agent information space the
Centre activates interaction between software
components by setting up the timeframes of
iterations. Therefore the Centre provides indirect
information management.
So the following 2 ideas can be proposed to
provide information management of multi-agent
intelligent scheduling:
1) implement the auction model for organization
of effective resource allocation in P2P distributed
information space;
2) manage agents’ negotiations in a process of
auction based resources allocation by varying time
intervals of the bidding iterations.
The difference of P2P auction from an ordinary
multi-agent auction is that the Center as P2P node
addresses each bidder individually that allows
implementing a method of agent’s adaptive
management by information. This method is based
on adaptive limiting, scoping and garbling being
applied to each node individually. For example, a
taxi dispatcher can inform different drivers only
about filtered orders to provide better cabs
geographical distribution and higher service level.
3 AN AUCTION MODEL FOR
AGENTS’ INTERACTION
In the following section the formal model of the
proposed approach is presented. For this purpose the
following variables are introduced:
0
C
is an initial price of a lot;
Niv
i
...1,
is a value of a lot for every particular
agent (N is agents’ total number);
ji
c
,
is a price of the bid made by an actor;
Mj ...1
is a number of iteration;
j
t
is an iteration’s duration.
The durations of iterations are not equal, as well as
not fixed, since they are started by new price
announcements made by the Center. New lot price
ji
C
,
is chosen as a maximum between all bids.
Auction is finished after the following time
passes since its start:
M
j
jA
tT
1
(1)
At each iteration the Centre is interacting with
agents using P2P principle: every message contains
a new bid proposal of lot price at the moment
ji
t
,
:
jijiji
tCs
,,,
,
(2)
Response messages can be sent by agents in turn:
jijiji
tcb
,,,
',
(3)
where
jijiji
cCc
,,,
.
Time required for an agent to make a decision is
,,
'
ij ij
tt
.
In such a model some agents can miss iteration and
make no bids. The goal of the Centre that organizes
Kk ..1
auctions can be defined as:
minmax,max
1
,
1
,
K
k
kA
K
k
Mi
i
TC
(4)
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