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1
Content available Production Scheduling for the Two Furnaces – One Casting Line System
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2020
|
Vol. 20, iss. 1
43--48
EN
The paper presents a production scheduling problem in a foundry equipped with two furnaces and one casting line, where the line is a bottleneck and furnaces, of the same capacity, work in parallel. The amount of produced castings may not exceed the capacity of the line and the furnaces, and their loads determine metal type from which the products are manufactured on the casting line. The purpose of planning is to create the processing order of metal production to prevent delays in the delivery of the ordered products to the customers. The problem is a mix of a lot-sizing and scheduling problems on two machines (the furnaces) run in parallel. The article gives a mathematical model that defines the optimization problem, and its relaxed version based on the concept of a rolling-horizon planning. The proposed approaches, i.e. commercial solver and Iterated Local Search (ILS) heuristic, were tested on a sample data and different problem sizes. The tests have shown that rolling horizon approach gives the best results for most problems, however, developed ILS algorithm gives better results for the largest problem instances with tight furnace capacity.
2
Content available System zarządzania a elastyczność organizacji – analiza literaturowa i koncetualizacja
Stawowy A.
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska
|
2018
|
z. 127
243--254
PL
Złożoność organizacji coraz częściej wskazywana jest jako jeden z głównych czynników blokujących rozwój organizacji. Zmieniające się trendy, rozwój technologii implikują zmiany na rynku, do których przedsiębiorstwa muszą się dostosować, aby przetrwać. Złożoność organizacji może blokować jej reakcję na wymagania otoczenia w odpowiednim czasie. Rozwiązaniem może być system zarządzania, który zapewniłby organizacjom niezbędną elastyczność. Aby badać system zarządzania, należy ustalić czym on w zasadzie jest. Analizując rozważania literaturowe można zauważyć, że nie ma jednolitej definicji pojęcia systemu zarządzania. Celem artykułu jest przegląd literaturowy, analiza oraz ponowna konceptualizacja pojęcia pod kątem elastyczności organizacji.
EN
Complexity of organizations is increasingly indicated as one of the 22 main factors blocking the organization's development. Changing trends, technology development imply changes in the market that businesses need to adapt to survive. The complexity of an organization can block its response to the environment demands at the right time. The solution could be a management system that would provide organizations with the necessary flexibility. To analyze the management system, it is necessary to determine what it is. When analyzing the literature one can see that there is no uniform definition of the management system concept. The purpose of this article is to review the literature, analyze and re-conceptualise it in terms of the organizational flexibility.
3
Content available Iterated Local Search for Foundry Lot-sizing and Scheduling Problem with Setup Costs
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2017
|
Vol. 17, iss. 4
161--164
EN
The paper presents a novel Iterated Local Search (ILS) algorithm to solve multi-item multi-family capacitated lot-sizing problem with setup costs independent of the family sequence. The model has a direct application to real production planning in foundry industry, where the goal is to create the batches of manufactured castings and the sequence of the melted metal loads to prevent delays in delivery of goods to clients. We extended existing models by introducing minimal utilization of furnace capacity during preparing melted alloy. We developed simple and fast ILS algorithm with problem-specific operators that are responsible for the local search procedure. The computational experiments on ten instances of the problem showed that the presence of minimum furnace utilization constraint has great impact on economic and technological conditions of castings production. For all test instances the proposed heuristic is able to provide the results that are comparable to state-of-the art commercial solver.
4
Content available Coordinated Production Planning and Scheduling Problem in a Foundry
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2017
|
Vol. 17, iss. 3
133--138
EN
In the paper, we present a coordinated production planning and scheduling problem for three major shops in a typical alloy casting foundry, i.e. a melting shop, molding shop with automatic line and a core shop. The castings, prepared from different metal, have different weight and different number of cores. Although core preparation does not required as strict coordination with molding plan as metal preparation in furnaces, some cores may have limited shelf life, depending on the material used, or at least it is usually not the best organizational practice to prepare them long in advance. Core shop have limited capacity, so the cores for castings that require multiple cores should be prepared earlier. We present a mixed integer programming model for the coordinated production planning and scheduling problem of the shops. Then we propose a simple Lagrangian relaxation heuristic and evolutionary based heuristic to solve the coordinated problem. The applicability of the proposed solution in industrial practice is verified on large instances of the problem with the data simulating actual production parameters in one of the medium size foundry.
5
Content available Application of Interval Arithmetic to Production Planning in a Foundry
Duda J., Stawowy A.
Archives of Foundry Engineering
|
2017
|
Vol. 17, iss. 1
41--44
EN
A novel approach for treating the uncertainty about the real levels of finished products during production planning and scheduling process is presented in the paper. Interval arithmetic is used to describe uncertainty concerning the production that was planned to cover potential defective products, but meets customer’s quality requirement and can be delivered as fully valuable products. Interval lot sizing and scheduling model to solve this problem is proposed, then a dedicated version of genetic algorithm that is able to deal with interval arithmetic is used to solve the test problems taken from a real world example described in the literature. The achieved results are compared with a standard approach in which no uncertainty about real production of valuable castings is considered. It has been shown that interval arithmetic can be a valuable method for modeling uncertainty, and proposed approach can provide more accurate information to the planners allowing them to take more tailored decisions.
6
Content available A Study of the Efficiency of Polish Foundries Using Data Envelopment Analysis
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2017
|
Vol. 17, iss. 1
223--227
EN
The article presents a study on the effectiveness of the foundries using Data Envelopment Analysis (DEA) method. The aim of the article is to analyze the usefulness of DEA method in the study of the relative efficiency of the foundries. DEA is a benchmarking technique based on linear programming to evaluate the effectiveness of the analyzed objects. The research was conducted in four Polish and two foreign plants. Evaluated foundries work in similar markets and have similar production technology. We created a DEA model with two inputs (fixed assets and employment) and one output (operating profit). The model was produced and solved using Microsoft Excel together with its Solver add-in. Moreover, we wrote a short VBA script to perform automating calculations. The results of our study include a benchmark and foundries’ ranking, and directions to improve the efficiency of inefficient units. Our research has shown that DEA can be a very valuable method for evaluating the efficiency of foundries.
7
Content available Applicability of Business Rules to Production Management in Foundries
Stawowy A., Duda J., Wrona R.
Archives of Foundry Engineering
|
2016
|
Vol. 16, iss. 1
85--88
EN
The size and complexity of decision problems in production systems and their impact on the economic results of companies make it necessary to develop new methods of solving these problems. One of the latest methods of decision support is business rules management. This approach can be used for the quantitative and qualitative decision, among them to production management. Our study has shown that the concept of business rules BR can play at most a supporting role in manufacturing management, but alone cannot form a complete solution for production management in foundries.
8
Content available Production Scheduling under Fuzziness for the Furnace - Casting Line System
Duda J., Stawowy A.
Archives of Foundry Engineering
|
2015
|
Vol. 15, iss. 4
29--32
EN
The problem considered in the paper is motivated by production planning in a foundry equipped with a furnace and a casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. However, contrary to the classic approach, we assumed the fuzzy nature of the demand set for a given day. The paper describes a genetic algorithm adapted to take into account the fuzzy parameters of simultaneous grouping and scheduling tasks and presents the results achieved by the algorithm for example test problem.
9
Content available Production Scheduling for the One Furnace – Two Casting Lines System
Basiura R., Duda J., Stawowy A.
Archives of Foundry Engineering
|
2015
|
Vol. 15, iss. 2 spec.
3--6
EN
The paper presents a scheduling production problem in foundry equipped with one furnace and two casting lines, which provides a number of different types of castings for a large number of clients. The amount of molten metal may not be greater than the capacity of the furnace and its load is a type of metal, from which the products are manufactured on automated casting lines. The purpose of planning is to create the processing order of metal, to prevent delays in the delivery of the ordered products to the customers. This problem is mixt of lot-sizing problem and scheduling problem on two machines (the lines) running in parallel. The article gives a mathematical model, which formally defines the optimization problem, and his relaxed version which is based on the concept of rolling-horizon planning. The proposed approaches were tested on the sample data.
10
Content available Multi-agent Approach to Production Scheduling in Foundries
Duda J., Stawowy A.
Archives of Foundry Engineering
|
2015
|
Vol. 15, iss. 2 spec.
17--22
EN
The paper describes a complete framework that uses a multi-agent approach for production scheduling in a foundry. Different types of autonomous agents have been designed, each playing a different role in the supply chain management of the fodundry, along with their responsibility and behavior in the system. In order to generate a proper and reliable schedule the agents negotiate with each other by sending messages compliant to FIPA ACL standard. A prototype of the system has been implemented in JADE and allowed to conduct preliminary simulation of the system. Although some agents some agents have been omitted in the prototype, it was possible to verify the main assumptions of the system, as well as, to indicate and discuss potential problems with its implementation into production practice.
11
Content available Mathematical Programming for Lot Sizing and Production Scheduling in Foundries
Duda J., Stawowy A., Basiura R.
Archives of Foundry Engineering
|
2014
|
Vol. 14, iss. 3
17--20
EN
The problem considered in the paper is motivated by production planning in a foundry equipped with the furnace and casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The quantity of molten metal does not exceed the capacity of the furnace, the load is a particular type of metal from which the products are made. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. The paper describes a mathematical programming model that formally defines the optimization problem and its relaxed version that is based on the conception of rolling-horizon planning.
12
Content available The methodology of virtual foundry developing
Brzeziński M., Stawowy A., Wrona R.
Archives of Metallurgy and Materials
|
2013
|
Vol. 58, iss. 3
867--870
EN
Systemic approach to design of factories requires that engineering, organisational and economic aspects should be considered concurrently. That prompts the need to develop a solution, based on the state-of-the-art IT technologies, to enable us to solve the problems associated with foundry production planning. The paper outlines a methodology of creating the simulation model of a virtual foundry, as a tool for foundry design. An integrative approach is suggested for development of a complete foundry model, enabling the design of more efficient production systems. The underlying principles of such models are discussed, the basic stages involved in the methodology are outlined and the range of its applicability is defined.
PL
Systemowe podejście do projektowania bądź rekonstrukcji systemów wytwarzania wymaga równoległego rozpatrywania zagadnień technologicznych, technicznych, organizacyjnych i ekonomicznych. Stwarza to potrzebę opracowania rozwiązania, opartego na najnowszych osiągnięciach technologii informatycznych, pozwalającego na kompleksowe rozwiązywanie problemu projektowania systemów produkcji odlewniczej. W pracy przedstawiono metodykę tworzenia (budowy) modelu symulacyjnego tzw. wirtualnej odlewni jako narzędzia projektowania zakładu odlewniczego. Zaproponowano iteracyjne podejście tworzenia kompleksowego modelu odlewni, dające w efekcie mozliwość projektowania bardziej wydajnych systemów wytwórczych. Przedstawiono zasady konstrukcji takiego modelu, opisano podstawowe etapy metodyki oraz określono mozliwości jej zastosowania.
13
Content available Optimization methods for lot-sizing problem in an automated foundry
Duda J., Stawowy A.
Archives of Metallurgy and Materials
|
2013
|
Vol. 58, iss. 3
863--866
EN
In the paper we studied a production planning problem in a mid-size foundry that provides tailor-made cast products in small lots for a large number of clients. Assuming that a production bottleneck is the furnace, a mixed-integer programming (MIP) model is proposed to determine the lot size of the items and the required alloys to be produced during each period of the finite planning horizon that is subdivided into smaller periods. As using an advanced commercial MIP solvers may be impractical for more complex and large problem instances, we proposed and compared a few computational intelligence heuristics i.e. tabu search, genetic algorithm and differential evolution. The examination showed that heuristic approaches can provide a good compromise between speed and quality of solutions and can be used in real-world production planning.
PL
W pracy przedstawiono problem planowania produkcji w odlewni średniej wielkości, która dostarcza odlewy na zamówienie dla dużej liczby klientów. W takim problemie konieczne jest określenie wielkości partii produkcyjnej oraz ilości i gatunku metalu w każdym okresie skończonego horyzontu planowania, który jest podzielony na mniejsze podokresy. Przy założeniu, że wąskim gardłem jest piec do topienia metalu, zaproponowano programowanie całkowitoliczbowe mieszane (Mixed-Integer Programming - MIP) jako model planowania i harmonogramowania produkcji w odlewni. Jako że użycie zaawansowanych komercyjnych solverów może być niepraktyczne dla złożonych problemów, zaproponowano i porównano trzy heurystyki inteligencji obliczeniowej tj. tabu search, algorytm genetyczny i ewolucja różnicowa. Eksperymenty obliczeniowe wykazały, że algorytmy heurystyczne zapewniają zadowalającą szybkość i jakość rozwiązań.
14
Content available Virtual factory as a method of foundry design and production management
Stawowy A., Wrona R., Brzeziński M., Ziółkowski E.
Archives of Foundry Engineering
|
2013
|
Vol. 13, iss. 1
113--118
EN
The paper outlines the methodology of virtual design of a foundry plant as a system. The most important stage in the procedure involves the development of a model defined as a set of data about the system. Model development involves two stages: defining the model’s architecture and specifying the model data in the form of parameters and input-output relationships. The structure is understood as configuration of machines and transport units, representing the sub-systems and system components. As the main purpose of the simulation procedure is to find the characteristics of the system’s behaviour, the merits of the iterative method involving analysis, synthesis and evaluation of results are fully explored.
15
Content available Production scheduling for the furnace - casting line system
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2013
|
Vol. 13, iss. 3
84--87
EN
The problem considered in the paper is motivated by production planning in a foundry equipped with the furnace and casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The quantity of molten metal does not exceed the capacity of the furnace, the load is a particular type of metal from which the products are made in the automatic casting lines. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. The paper describes two computational intelligence algorithms for simultaneous grouping and scheduling tasks and presents the results achieved by these algorithms for example test problems.
16
Content available Models and algorithms for production planning and scheduling in foundries - current state and development perspectives
Stawowy A., Duda J.
Archives of Foundry Engineering
|
2012
|
Vol. 12, iss. 2
69-74
EN
Mathematical programming, constraint programming and computational intelligence techniques, presented in the literature in the field of operations research and production management, are generally inadequate for planning real-life production process. These methods are in fact dedicated to solving the standard problems such as shop floor scheduling or lot-sizing, or their simple combinations such as scheduling with batching. Whereas many real-world production planning problems require the simultaneous solution of several problems (in addition to task scheduling and lot-sizing, the problems such as cutting, workforce scheduling, packing and transport issues), including the problems that are difficult to structure. The article presents examples and classification of production planning and scheduling systems in the foundry industry described in the literature, and also outlines the possible development directions of models and algorithms used in such systems.
17
Content available remote Genetic programming for the prediction of tensile strength of cast iron
Duda J., Stawowy A.
Archives of Foundry Engineering
|
2011
|
Vol. 11, iss. 4
31-34
EN
In this paper we propose genetic programming (GP) to predict tensile strength of ductile cast iron. The chemical composition and pouring temperature were used as explanatory input variables (parameters), while tensile strength as dependent output variable (response). On the basis of real data set collected in a one of the Polish foundries, two different models for output variable were developed by genetic programming. Statistical analysis of obtained results and two test cases were employed to compare the accuracy of the GP model with the neural network (NN) model and a linear multiple regression model. The comparison demonstrated that the GP outperforms regress ion techniques, while it is generally worse than NN. Nevertheless GP can be a powerful tool for predicting the mechanical properties of cast iron as it provides a mathematical model, which can be further analyzed.
18
Content available remote Classification of foundry clients using business rules approach
Stawowy A., Wrona R., Ronduda M.
Archives of Foundry Engineering
|
2011
|
Vol. 11, iss. 4
145-148
EN
The paper presents the application of business rules approach for the classification of foundry clients taking into account the economic and technological attributes. Business Rules Management (BRM) systems allow non-technical business people to change the rules, analyze them for errors, and test and simulate them for impact analysis. Although BRM is focused on business processes improvement, it is possible to use this approach in technology management. The model of classification problem, and the knowledge base as a set of decision tables are presented in the paper. The results indicate that the proposed business rules tool REBIT, developed by AGH team as the project co-funded by the European Union, is feasible as a complete knowledge base and technology management method.
19
Content available remote Casting process selection using business rules approach
Stawowy A., Macioł A., Wrona R.
Archives of Metallurgy and Materials
|
2010
|
Vol. 55, iss. 3
927-934
EN
This paper presents the application of business rules idea for the selection of casting process taking into account the economic and technological requirements. Business Rules Management (BRM) systems allow non-technical business people to change the rules, analyze them for errors, and test and simulate them for impact analysis. Although BRM is focused on business processes improvement, it is possible to use this approach in technology management. The model of technology selection problem, the knowledge base as a set of rules and the solutions of exemplar cases are presented in the paper. The results indicate that the proposed business rules tool is feasible as a complete knowledge base and technology management method.
PL
W pracy przedstawiono sposób rozwiązywania problemu doboru technologii wykonania odlewu przy użyciu koncepcji reguł biznesowych (BRM - Business Rules Management). Systemy BRM pozwalają użytkownikowi-menedżerowi, który nie jest programista, formułować, aktualizować weryfikować i symulowac reguły w sposób zbliżony do języka naturalnego. Aczkolwiek BRM jest ukierunkowana na poprawe procesów biznesowych, z powodzeniem można stosować te koncepcje w zarządzaniu technologia. Przedstawiony został model problemu decyzyjnego doboru technologii, zestaw reguł służących do jego rozwiązania oraz przykłady rozwiązania konkretnych zadań. Uzyskane wyniki dowiodły możliwości zapisu wiedzy i wsparcia zarządzania technologią z wykorzystaniem nowoczesnych koncepcji zarządzania i informatyki.
20
Content available remote An application of advanced information technology in foundry engineering
Macioł A., Wrona R., Stawowy A.
Archives of Foundry Engineering
|
2010
|
Vol. 10, iss. 2
83--88
EN
The main goal of our lately researches bas been to prove that application of technological knowledge can be supported by artificial intelligence tools and internet techniques. Computer aided systems for technological process design presented in literature have a priori defined, fixed structure. The aim of our work was to develop an open system that guarantees easy knowledge changing and extending. We use the original method elaborated in University of Science and Technology called IwQ (Inference with Queries) as an inference engine for business and technological rules management. We also consider storage of data in relational database as a tool for ontology development. Application of metamodel in predefining information structure enabled flexible recording of the significantly differing information resources.
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