title = "Parallelization of vehicle routing algorithms by using
database with domain-specific embedded functions",
title2 = "Paralelizacija algoritama za rjesavanje problema
usmjeravanja vozila koristenjem baza podataka s
ugradenim domenski usmjerenim funkcijama",
school = "Department of Applied Computing, University of
Zagreb",
year = "2017",
address = "Croatia",
keywords = "genetic algorithms, genetic programming, Process
Computing",
URL = "https://urn.nsk.hr/urn:nbn:hr:168:300689",
size = "110 str.",
abstract = "Increasingly complex variants of the vehicle routing
problem with time windows (VRPTW) are coming into
focus, alleviated with advances in the computing power.
VRPTW is a combination of the classical travelling
salesman and bin packing problems, with many real world
applications in various fields. From physical resource
manipulation planning to virtual resource management in
the ever more popular cloud computing domain. The basis
for many VRPTW approaches is a heuristic which builds a
candidate solution that is subsequently improved by a
search or optimization procedure. The choice of the
appropriate heuristic may have a great impact on the
quality of the obtained results. In this work genetic
programming is used to evolve a suitable heuristic to
build initial solutions for different objectives and
classes of VRPTW instances. Additionally 2-phase
parallel algorithm has been proposed to improve initial
results obtained by genetic programming. Proposed
solution is based on the divide and conquer paradigm,
decomposing problem instances into smaller, mutually
independent sub-problems which can be solved using
traditional algorithms and integrated into a global
solution of reasonably good quality. The results show
great potential, since this method is applicable to
different problem classes and user-defined performance
objectives. It has been noticed that sometimes results
for vehicle routing problem could not be used in real
world applications, due to dynamic behaviour of
transport systems (incidents or traffic congestion).
Improving traffic control has been studied in this
work. Solving traffic congestions represents a high
priority issue in many big cities. Traditional traffic
control systems are mainly based on pre-programmed,
reactive and local techniques. This work presents an
autonomic system that uses automated planning
techniques instead. These techniques are easily
configurable and modified, and can reason about the
future implications of actions that change the default
traffic lights behaviour. The proposed implemented
system includes some autonomic properties, since it
monitors the current traffic state, detects whether the
system is degrading its performance, sets up new sets
of goals to be achieved by the planner, triggers the
planner that generates plans with control actions, and
executes the selected courses of actions. The obtained
results in several artificial and real world data-based
simulation scenarios show that the proposed system can
efficiently solve traffic congestion.",
abstract = "Povecanjem brige o okolisu i teznjom za smanjenjem
troskova transporta problem usmjeravanja vozila (VRP)
postaje sve vaznija stavka u razvijenim drustvima.
Navedeni problem je kombinacija nekoliko klasicnih
optimizacijskih problema (problem trgovackog putnika,
problem pakiranja). U radu je istrazeno nekoliko
inovativnih metoda koje bi se mogle primijeniti na
sirokom spektru problema iz stvarnog svijeta
(prikupljanje otpada, dostava ...). Osnovne poteskoce
na koje se nailazi su vrijeme potrebno za pronalazenje
prihvatljivih rjesenja i iznimno velik prostor
pretrazivanja rjesenja. Kako bi se ostvarilo bolje
rezultate od postojecih potrebno je bolje usmjeravanje
prilikom pretrazivanja kako se ne bi trosilo vrijeme na
istrazivanje nekvalitetnih rjesenja. Koristeci
geneticko programiranje i pohlepne funkcije moguce je
brzo stvoriti pocetno rjesenje cjelobrojnog problema
usmjeravanje vozila s ciljem posluzivanja odredenih
lokacija odredenim skupom vozila, te brzo poboljsanje
tako dobivenih pocetnih rjesenja. Naknadno poboljsanje
pocetnih rjesenja moguce je opisanim paralelnim
algoritmima za usmjeravanje vozila. Nakon sto su
dobiveni rezultati za problem usmjeravanja vozila,
uoceno je da te iste rezultate ponekad nije moguce
primijeniti u stvarnom svijetu. Novonastali problem
rijesen je stvaranjem jedinstvenog inteligentnog
autonomnog prometnog sustava koji ima mogucnosti
pratiti stanje prometa, otkriti moguce probleme,
promijeniti stanje prometa koristenjem automatiziranog
planiranja u cilju ostvarivanja bolje protocnosti
prometa. Koristenjem predlozenog sustava pokazano je
efikasnije upravljanje prometnim sustavima.",