ECONOMETRIC PATTERNS AND METHODS USED FOR ANALYSIS OF TECHNOLOGICAL INNOVATIONS IN WORKSHOPS AND PRODUCTION DEPARTMENTS EQUIPPED WITH FLEXIBLE MANUFACTURING SYSTEMS - Polish Journal of Management Studies

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ECONOMETRIC PATTERNS AND METHODS USED FOR ANALYSIS OF TECHNOLOGICAL INNOVATIONS IN WORKSHOPS AND PRODUCTION DEPARTMENTS EQUIPPED WITH FLEXIBLE MANUFACTURING SYSTEMS

Abstracts > Vol 3

ECONOMETRIC PATTERNS AND METHODS USED FOR ANALYSIS OF TECHNOLOGICAL INNOVATIONS IN WORKSHOPS AND PRODUCTION DEPARTMENTS EQUIPPED WITH FLEXIBLE MANUFACTURING SYSTEMS

Dima I. C., Man M., Nowicka-Skowron M., Grabara I.  


Abstract

Pursuant to the analysis of the assessment method of the structures of the production process, in the construction of machines, we find that, due to the requirements of diversification  of assortments and features of products, criteria of the quality level and work productivity, the reduction of fabrication costs, the structure of the production process develops continuously. Starting from workshops specialized on technological procedures,  the structure developed onto production lines in a sole object flow, then onto production lines in a multi-object flow, and, currently, onto flexible production forms.
To this purpose, flexible fabrication cells develop. The latter form develops continuously, but especially after the accomplishment of machine-tools with number command. Thus, we pass from production structures in automatic rigid  flow lines, efficient for mass and wide-range production, to flexible structures, especially efficient in low and medium-range production.

Keywords: Analysis, workshops, econometric patterns, flexible manufacturing system

Introduction

For the production of unique pieces, processing is extended on machine-tools with number command, replacing manually operated universal machine-tools. Figure 3 presents the scheme of the current tendencies of the evolution of production structures  in the construction of machines and devices.
Considering a flexible fabrication system, we see that it allows the processing of pieces which are different in terms of shape and dimensions, in a determined range. This possibility creates conditions for the accomplishment  of variable products, under high saving conditions.
Savings are made because the degree of usage of production means increases, the fabrication time is shortened, the route and duration of transports are reduced, intermediate storage expenses decrease, the area required for production  is reduced, the processing process may be systematised, proper conditions for continuous work are created and direct expenses are reduced.
Within the structures of organisation of production means, one of the forms which develop quickly is that of the “cellular” structure, a system presenting the widest conditions for flexible manufacturing.
At the same time, systems in flow start to develop, provided with computer-assisted management equipment.



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Summary

The replacement of machines is based on certain mathematical methods for explaining such replacement, but these methods do not consider tangible factors.
The issues related to the machine’s replacement, considering the degree of knowledge thereof may be: determinist issues, probabilistic ~ stochastic issues.
Determinist issues are those when the time and implications of the replacement action may be certainly determined (known). For instance, the situation of a machine whose operating costs increase in direct proportion to the  duration of use. In order to reduce this cost, the machine must be replaced, so that the operating cost shall tend to increase, as shown in figure 17.Probabilistic situations are those when the time and implications of the replacement action cannot be  exactly determined. Let us consider that the machine has two states: proper operating state (F) and non-operating state (N). The probabilistic law, describing the transition from state F to state N may be described by the distribution  of time between the end of the replacement action and the fall of the equipment.
The decisions to replace machines in case the fall of machines follows a probabilistic law are those decisions where the risk is given by the impossibility to exactly determine the moment when such machine falls or the transition  moment from state F to state N. Another source of risk is given by the impossibility to determine the state of the equipment when no inspection or other maintenance activity occurs. We consider that there are only two states of the equipment F and N, which are always known.We have to determine the times when the action of replacement of machines should occur.This is called machine replacement policy. In this case, we are interested in the optimal replacement policy, i.e.  the one maximising or minimising certain economic criteria, such as:profit, total cost, non-operating time
Let us consider thatthe activity of replacement of the equipment results in the further production, at the same quality level, of the same products and services previously produced by the replaced machine. Hence, fall distributions  and related costs are the same for all models (except for the model which considers the technological improvement of the machine).
Preventive replacement for fixed assets implies two conditions:
the total replacement cost shall be higher after the fall itself at the moment when the preventive replacement is made;
the fall rate of the equipment increases instead of remaining constant. In order to prove this, let us consider than an equipment has a constant fall rate and follows a negative exponential law. In this case, the replacement  of the machine before the fall itself does not affect the chance that the equipment may fall at the following moment. In the case of negative exponential distribution, preventive replacement represents a loss of money and other resources.
Therefore, preventive replacement is only justified when the rate of replacement grows. In case the machine is damaged, the specialist in the department should increase the preventive replacement activity. This may be a mistake,  as the preventive replacement of machines (or machine components) is not always justified.


References

[1].   Dima I.C., Man M. Management of industrial activity, Publishing House of the Romanian Academy, Bucharest, Romania 1999.
[2].   Dima I.C., Managementul industrial (Industrial Management), National Publishing House, Bucharest, Romania 2000.
[3].   Dima I.C., Modrak V., Grabara I. Elemente de management operaţional industrial (Elements of industrial operational management), Publishing House of Valahia University, Targoviste, Romania 2010.
[4].   Dima I.C., Nowicka M., Grabara I., Modrak V. Utilizarea elementelor de logistică în managementul operaţional industrial. (Using the elements of logistic in industrial operational management), Publishing House of Valahia University,  Targoviste, Romania 2010.
[5].   Dima I.C., Modrak V., Nowicka-Skowron M., Grabara J. Elemente de logistica utilizate in managementul operational industrial, Apeiron Eu, Presov, 2010.
[6].   Grabara J., Position of Innovation in Poland on European Union Countries Background. [in:] Aktualne otazky svetovej ekonomiky a politiky. Medzinarodne vzt'ahy 2009. Zbornik prispevkov z 10. medzinarodnej vedeckej konferencie. Zamok Smolenie 2010.
[7].   Kisel’áková D., Kisel’ák A., Importance of Use of Knowledge in Application of Methods of Company Benchmarking.  [in:] Management 2010 – Knowledge and Management in Times of Crisis and Ensuing Development. Part I. Prešov : University of Prešov, Faculty of Management, Slovak Republic, 2010. p. 37 - 45

METODY ORAZ MODELE EKONOMETRYCZNE WYKORZYSTYWANE DO ANALIZY INNOWACJI TECHNOLOGICZNYCH W WYTWÓRNIACH I DZIAŁACH PRODUKCYJNYCH WYPOSAŻONYCH W ELASTYCZNE SYSTEMY  PRODUKCYJNE

Streszczenie


Na podstawie analizy metod oceny struktury procesu produkcyjnego, w konstrukcji maszyn, okazuje się, że ze względu na wymogi dywersyfikacji asortymentu i cechy  produktów, kryteria poziomu jakości i wydajności pracy, obniżenie kosztów produkcji, struktura procesu produkcji rozwija się w sposób ciągły. Począwszy od wytwórni wyspecjalizowanych w procedurach  technologicznych, z rozwiniętą strukturą na liniach produkcyjnych w przepływie pojedynczego obiektu do linii produkcyjnych z przepływem wielu obiektów, a obecnie do elastycznych form produkcji. W tym celu rozwijają się komórki elastycznego wytwarzania. Ostatnia forma rozwija się w sposób ciągły, zwłaszcza po wykonaniu obrabiarek z poleceniem numerycznym. W ten sposób przechodzimy od struktury produkcji w automatycznych sztywnych  liniach przepływu, wydajnych dla masowej i szerokiej zakresowo produkcji, do struktur elastycznych, szczególnie skutecznych w produkcji niskiego i średniego zasięgu.




 
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