In the paper manufacturing automation systems is divided into two classes: rigidautomation and flexible automation. The paper intends to highlight the decrease of transportation timewithin production processes as a result of transportation optimization. The objectives of currentindustry are: product quality and productivity increase, decreasing delivery time, the need to improveworking conditions, the use of specifications for each product. They are analyzed by tracing thetransportation time of a production company form Alba Iulia.manufacturing, transportation optimization, Petri, Markov process, systems flexibility

Elisabeta Mihaela Ciortea

English

Research Papers in Economics

Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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TRANSPORT CHARACTERISTICS IN AUTOMATED PRODUCTION 
 
 
Elisabeta Mihaela Ciortea
1  
 
 
ABSTRACT:  In  the  paper  manufacturing  automation  systems  is  divided  into  two  classes:  rigid 
automation and flexible automation.  The paper intends to highlight the decrease of transportation 
time  within  production  processes  as  a  result  of  transportation  optimization.  The  objectives  of 
current industry are: product quality and productivity increase, decreasing delivery time, the need 
to improve working conditions, the use of specifications for each product. They are analyzed by 
tracing the transportation time of a production company form Alba Iulia.  
 
Key words: manufacturing, transportation optimization, Petri, Markov process, systems flexibility  
 
JEL codes:L69 
 
 
Introduction  
Automation  applies  to  all  sub  components  of  the  production  system  namely  processing 
subsystem, subsystem assembly / installation, handling subsystem, the subsystem storage / storage 
subsystem processing and product quality control, subsystem planning and programming process 
via computer management subsystem for information processing. 
  Flexibility of construction may be limited by lack of financial flexibility, while significant 
manufacturing flexibility can encourage and commercial flexibility. 
  Information systems become  more complex so without inflexibility in the system. With 
increasing complexity in the system too few people understand the system reason why the tendency 
to avoid information systems flexibility. Complex information systems are designed to increase the 
flexibility of information, but in practice there is a decrease in these systems. 
  In order to achieve production flexibility can be used for a range of methods, including 
equipment manufacturing, product creation, work organization, planning and control procedures, 
materials management and information technology. 
 
Manufacturing process simulation 
In order to simulate the manufacturing process we have chosen Matlab package, [9], [10], 
which is comprised from pntool library, which can be achieved through modeling the graph under 
examination. 
Since the time of manufacture are very large and difficult process simulation is carried out 
we have divided the graph according to the transmission system. 
The  sequence  of  events  is  reduced  to  a  mere  ordering  of  their  appearance.  Simulation 
involves the execution of consecutive transitions, as rule enforcement transitions [14] [15]. Toolbox 
PN environment stores all transitions validated in MATLAB system, but the transitions are made at 
all, one by one. Function that makes the transition to be executed is determined by priorities or 
probabilities assigned to transitions in conflict. 
Because  manufacturing  is  very  high  and  use  four  types  of  transportation  (forklift, 
Electrostivuitor, truck and portpalet) have divided the whole system into three sections. The work is 
considered the last section of the system. 
Section III: 
                                                       
1 Universitatea “1 Decembrie 1918”, str. N.Iorga, 13 14, ciortea31mihaela@yahoo.com Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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Fig. no. 1 – Petri net for Section III 
 
SECTION III stroke auxiliary: 
 
fig. no. 2 - Petri net for stroke auxiliary SECTION III 
 
For networks with timed position (timed P), positions may be added one time, carriers will 
be reserved for that time period in appropriate positions, immediately upon arrival. For simulation, 
all transitions that can be executed because the current marking are performed simultaneously. A 
transition  can  be  executed  several  times,  as  marking  the  positions  of  entry  and,  theoretically, 
successive execution of a transition are separated by a very small delay [14] [15]. 
Appropriate functions available in MATLAB Toolbox can be used for time intervals added 
positions. 
SECTION III: Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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fig. no.3 - Petri net corresponding to section III 
 
 
 
 
 
 
fig. no.4: Queue Length indicator trends corresponding positions analyzed (continuous line - 
the current value. Dashed - the total value obtained by the average length of simulation) 
 Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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fig. no.5: Appropriate graphical representation shown in Section III open window of Petri Net 
Toolbox for analysis max plus 
 
If stochastic networks, only exponential type distributions can be used to add time intervals 
of transitions. For transitions  in conflict,  the  shortest duration  is one  that allows the choice of 
transition to be executed without using priorities or probabilities. Do not allow multiple execution 
of the same transitions, even if one allows content marking the positions of entry, this implies that 
the transition to be executed once, and after the time allowed runs can be executed again if the 
current marking is appropriate.  
Sequential transition of executed ease controlled exclusively by the intervals of exponential 
type to ensure equivalence to Markov chains. By default, executing the transition rate (meaning the 
inverse average duration) is dependent on marking, but the user can select a bookmark independent 
operation. 
By using generalized stochastic Petri networks to obtain model production system under 
analysis.  Execution  times of transitions are  distributed in an exponential law which provides a 
marking graph of Petri network, which is a homogeneous Markov process. 
 
fig. no.6: The average length of storage elements 
 Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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fig. no.7: The average length of employment cart 
 
fig. no.8: The average length of employment stochator 
 
fig. no.9:The average length of return portpalet 
Based on the analysis has suggested options for the location in new technology. Given the 
flow transmission, sequence of operations can not be changed, it can only reduce the distance and 
transportation equipment are subject to change. 
The  technological  flow  improvements  are  not,  the  sequence  phase  is:  sitar,  isostatic 
pressing, firing the biscuit, biscuitare, glazing, firing 2, sort produced white, decoration, decoration 
firing,  the  final  sorting,  packing,  storage  of  finished  products  warehouse,  is  the  same  for  all 
companies producing ceramics. 
Since  the  combustion  furnace  2,  the  porcelain  mass  is  transported  to  the  sorting  table Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
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portpalet to white product. Standards in force ore/100 sorts 0.213 pcs (3750 pcs / 8 hours). Dishes 
are handled with portpalet to decoration, carried out 2.155 ore/100buc (371 pcs / 8 hours). 
The burning oven decor, continues handling portpalet the final sorting process plates with 
0.26 ore/100 pcs (3065 pcs / 8 hours). After the final sorting, the plates are transported to be packed 
0.366 hours / 100 pcs (2185 pcs / 8 hours). After packing the boxes are transported portpalet the 
warehouse, from where they will be distributed. 
 
Conclusions  
In timed Petri networks is considered viable properties and the edges are some of the most 
important distributed system under analysis. The results help to find and study of as many timed 
Petri networks which may be made effective analysis. 
Most common hypothesis is that  the  delay is distributed according  to exponential  laws. 
Marking a stochastic Petri net is a homogeneous markov process, so each stochastic Petri networks 
can be associated a homogeneous Markov chain. 
Of those given the observed decrease in transport type and string length changes of the 
workplace location. 
The results obtained confirm the correctness of the method chosen. It is noted, the results 
obtained  a  new  method  of  placement  of  work  stations  to  minimize  transport  distances,  which 
implies a more efficient coordination of the transport system, leading to the optimization system. 
The graph is done using: 
  Netemporizate Petri net, where available instruments provide information on the mathematical 
model (the incidence  matrix, graphic design, text  and presentation style of  knot invariants and 
transition). 
  Timed Petri net. Using tools to obtain graphics library pntool time evolution of indicators Queue 
Length appropriate processing positions.  The continuous line represents the present value and the 
dashed overall value obtained by the average length of simulation. 
Applying  the  terms  of  product  manufacturing  and  transportation  times  obtained  by 
measuring  the  spot  to  get  graphics that  show  the  average  times  of  transport  activities,  but  the 
average duration of manufacturing development according to time periods for transmission using 
the parameters as lots of finished products. 
  Stochastic Petri net used as parameters the mean exponential distribution to model the availability 
of transport assigned position. These are graphics on the development of terms of manufacturing 
environments, the average length of employment development equipment, graphic representation of 
the average duration of transmission for each carrier separately and graphic representation of the 
average number of carriers from storage. 
Theoretical results obtained can be directly implemented in the manufacturing process.  
By  optimizing  the  transport  system  proposed  has  achieved  a  reduction  in  waiting  time, 
transportation time, reduce the string length of waiting and easier coordination burning stoves. 
 
References 
1.  Abrudan I., „Economia proiectării sistemelor flexibile de fabricaţie”, Editura Universitatea 
Tehnică din Cluj Napoca, 1993 
2.  Bănică Ion, „Reţele de comunicaţii între calculatoare”, Editura TEORA, Bucure ti, 2000, 
ISBN 973 601 683 8 
3.  Bojan  I.,  „Sisteme  flexibile  de  producţie.  Optimizarea  proiectării   i  managementul 
proceselor”, Editura DACIA, Cluj Napoca, 1999 
4.  Bojan Ioan, „Sisteme flexibile de producţie”, Editura DACIA, 1999, ISBN 973 35 0781 4 
5.  Calefariu  G.,  „Optimizarea  proceselor  de  fabricaţie”,  Editura  Universităţii  Transilvania 
Bra ov, 2002 
6.  Camerzan Inga, „Proprietăţi structurale ale reţelelor Petri temporizate”, Teza de doctor în Annales Universitatis Apulensis Series Oeconomica, 11(1), 2009 
 
  230
informatică, Universitate de Stat din Tiraspol, Chi inău, 2007 12 15 
7.  Ciortea Elisabeta Mihaela, „Analiza sistemelor automate de producţie”, Referat de doctorat 
I, Universitatea Tehnică Cluj Napoca, 2004 
8.  Ciortea Elisabeta Mihaela, „Contribuţii privind dezvoltarea algoritmilor pentru optimizarea 
transportului în celule flexibile”, Referat de doctorat III, Universitate Tehnică Cluj Napoca, 
2006 
9.  Ciortea  Elisabeta  Mihaela,  „Particularităţi  privind  proiectarea  sistemului  de  manipulare 
materială, Sesiunea Anuală de Comunicări  tiinţifice a Universităţii din Oradea, 2004 
10. Ciortea  Elisabeta  Mihaela, „The  study  for  transport  in  flexible  cells”, 
TH 6   International 
Conference of phd Students, 12 18 August 2007, Miskolc, ISBN 978 963 661 779 0 
11. Ciortea Elisabeta Mihaela, Morar Liviu, „Analysis of the influence of the transportation 
system in increasing the performances of the production system”, ACTA UNIVERSITATIS 
CIBINIENSIS, Vol. LII, Technical Series, Sibiu, 2005 
12. Ciortea  Elisabeta  Mihaela,  Morar  Liviu,  Pâslă  Adrian,  Vlad  Camelia,  „Petri net  based 
approaches  to  flexible  manufacturing  systems”,  Internationa  Conference  on  Economic 
Engineering and Manufacturing Systems (ICEEMS 2007), 25 26 Octombrie 2007, Bra ov, 
RECENT 2007, ISSN 1582 0246 
13. Kovacs F., „Manipulatoare, roboţi  i aplicaţiile lor industriale”, Editura Facla, Timi oara, 
1982 
14. Păstrăvanu  Octavian,  „Sisteme  cu  evenimente  discrete.  Tehnici  calitative  bazate  pe 
formalismul reţelelor Petri”, Editura MatrixRom, Bucure ti, 1997, ISBN 973 9254 61 6 
15. Păstrăvanu Octavian, Matcovschi Mihaela, Mahulea Cristian, „Aplicaţii ale reţelelor Petri în 
studierea Sistemelor cu evenimente discrete”, Editura Gh. Asachi, 2002, ISBN 973 8292 
86 7 
16. Ciortea  Elisabeta  Mihaela,  „Contribuţii  privind  optimizarea  transportului  în  sisteme  de 
fabricaţie”, Teza de doctorat, 2008, Cluj Napoca 
 
 

Analiza sistemelor automate de producţie”, Referat de doctorat I, Universitatea Tehnică Cluj Napoca,

Aplicaţii ale reţelelor Petri în studierea Sistemelor cu evenimente discrete”, Editura Gh. Asachi,

Contribuţii privind dezvoltarea algoritmilor pentru optimizarea transportului în celule flexibile”, Referat de doctorat III,

Contribuţii privind optimizarea transportului în sisteme de fabricaţie”, Teza de doctorat,

Economia proiectării sistemelor flexibile de fabricaţie”, Editura Universitatea Tehnică din Cluj Napoca,

Manipulatoare, roboţi i aplicaţiile lor industriale”, Editura Facla,

Morar Liviu, „Analysis of the influence of the transportation system in increasing the performances of the production system”,

Optimizarea proceselor de fabricaţie”, Editura Universităţii Transilvania Bra ov,

Particularităţi privind proiectarea sistemului de manipulare materială, Sesiunea Anuală de Comunicări tiinţifice a Universităţii din Oradea,

Proprietăţi structurale ale reţelelor Petri temporizate”, Teza de doctor în Annales Universitatis Apulensis Series Oeconomica,

Reţele de comunicaţii între calculatoare”, Editura TEORA, Bucure ti,

Sisteme cu evenimente discrete. Tehnici calitative bazate pe formalismul reţelelor Petri”, Editura MatrixRom, Bucure ti,

Sisteme flexibile de producţie. Optimizarea proiectării i managementul proceselor”, Editura DACIA, Cluj Napoca,

Sisteme flexibile de producţie”,

The study for transport in flexible cells”,

Vlad Camelia, „Petri net based approaches to flexible manufacturing systems”,

TRANSPORT CHARACTERISTICS IN AUTOMATED PRODUCTION

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TRANSPORT CHARACTERISTICS IN AUTOMATED PRODUCTION

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