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  1. 34 Przegląd Komunalny
  2. 18 Archives of Foundry Engineering
  3. 16 Magazyn Autostrady
  4. 11 Ekonomia Menedżerska
  5. 8 Archives of Control Sciences
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  1. 185 Duda J.
  2. 20 Stawowy A.
  3. 9 Wasilewski M.
  4. 5 Duczkowska-Kądziel A.
  5. 5 Pobożniak J.
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  1. 1 2020
  2. 4 2018
  3. 8 2017
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  5. 7 2015
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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
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2020
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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 Wykorzystanie własnych zasobów obliczeniowych przedsiębiorstwa w procesie planowania produkcji
Dłubacz W., Duda J.
Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Technika, Informatyka, Inżynieria Bezpieczeństwa
|
2018
|
T. 6
355--369
PL
W artykule przedstawiony został nowoczesny system obliczeń rozproszonych, umożliwiający łatwe wykorzystanie dostępnych zasobów obliczeniowych przedsiębiorstwa. Opracowany system pozwala na przygotowanie planów produkcji w oparciu o różne modele matematyczne. Do rozwiązania problemów został wykorzystany rozproszony algorytm genetyczny z różnymi reprezentacjami chromosomu oraz operatorami genetycznymi, dostosowanymi do specyfiki danego problemu. W ten sposób wykazana została uniwersalność zaproponowanego systemu i jego zdolność do rozwiązywania rzeczywistych problemów zarządzania produkcją.
EN
The article presents a modern system of distributed computing, allowing easy use of available computational resources of the company. The developed system allows for the generation of production plans based on various mathematical models. A distributed genetic algorithm with different solution representations and different genetic operators tailored to the specific problem is used to solve the problems. In this way, the universality of the proposed system and its ability to solve real problems of production management were demonstrated.
3
Content available Bank policies towards SME sector in Poland and selected countries worldwide
Duda J., Woźniak M.
Managerial Economics
|
2018
|
Vol. 19, no. 1
25--47
EN
Small- and medium-sized enterprises (SMEs) are very significant for the economy. However, they face many problems when trying to finance their development. In connection to the above, the authors set four research questions that are connected with bank policies towards SMEs. Then, they make an analysis in order to answer the questions. The conclusions, recommendations. and limitations are presented at the end of the paper.
4
Analiza drgań gruntu spowodowanych przejazdami pociągów w aspekcie wpływu na obiekty budowlane i ludzi
Duda J.
Inżynieria i Budownictwo
|
2018
|
R. 74, nr 2
87--90
PL
Przedstawiono metodykę oraz wyniki przeprowadzonych badań. Analizowano przyspieszenia oraz prędkości drgań. Przeprowadzono analizę przebiegów czasowych oraz analizę widmową w tercjowych pasmach częstotliwości. Porównano z wynikami badań opisanymi w literaturze, dotyczącymi drgań od przejazdów pociągów, prac strzałowych oraz wstrząsów górniczych.
EN
Paper presents both the methodology and results of the research. Acceleration and velocity of vibration were analysed. Time histories and one-third octave frequency bands spectra were analysed. Results were compared to case studies presented in literature, concerning railway, quarring and mining induced ground vibration.
5
Content available Lyapunov matrices approach to the parametric optimization of a system with two delays and a PD-controller
Duda J.
Archives of Control Sciences
|
2018
|
Vol. 28, No. 4
585--600
EN
In the paper the parametric optimization problem for a linear system with two delays and a PD-controller is presented. In the parametric optimization problem the quadratic performance index is considered. The value of the quadratic index of quality is calculated due to the Lyapunov functional and is equal to the value of that functional for the initial function of the neutral system with two delays. The Lyapunov functional is determined by means of the Lyapunov matrix.
6
Content available Sposób ograniczenia strat cieplnych bypassa
Duda J., Kołosowski M., Tomasiak J.
Prace Instytutu Ceramiki i Materiałów Budowlanych
|
2017
|
R. 10, nr 31
28--40
PL
Wraz z rozwojem nowych, suchych metod wypalania klinkieru w piecach z wielostopniowymi podgrzewaczami surowca, pojawiły się nowe problemy technologicznie związane z tworzeniem się narostów w wymiennikach ciepła. Narosty te powstają w wyniku obiegu składników lotnych: alkaliów, siarki i chloru. Istotnym źródłem składników lotnych (oprócz surowca i pyłu węglowego) są paliwa alternatywne. Obserwowany w ostatnich latach intensywny wzrost udziału paliw alternatywnych w procesie wypalania klinkieru spowodował konieczność ograniczenia obiegu składników lotnych w instalacji piecowej poprzez zastosowanie bypassa, polegającego na wyprowadzeniu w zależności od zawartości składników lotnych 3–20% części gazów poza piec, z pominięciem wymiennika ciepła. Każdy procent bocznikowanych gazów powoduje wzrost zużycia ciepła w procesie wypalania o ok. 20–25 kJ/kgkl. W związku z tym dąży się do ograniczenia wielkości bypassa. Efekty ekologiczne i ekonomiczne z wykorzystania paliw alternatywnych powodują, że udział tych paliw stale rośnie, co skutkuje wzrostem obiegu składników lotnych i tym samym istnieje konieczność zwiększenia wielkości bocznikowanych gazów. W artykule przedstawiono jeden ze sposobów ograniczenia strat cieplnych w procesie wypalania klinkieru wynikających z zastosowania bypassa, polegający na wykorzystaniu entalpii gazów bypassowych do produkcji energii elektrycznej.
EN
The development of new, dry methods of clinker production in furnaces with multistage raw material heaters has resulted in new technological problems related to accretions building up in the heat exchangers. Such accretions form because of the circulation of volatile components: alkali, sulphur and chlorine. Beside raw material and coal dust, a lot of volatile components come from alternative fuels. Recent years have seen a significant increase in the use of alternative fuels in the clinker burning process, which made it necessary to restrict the circulation of volatile components in the furnace system with a bypass, which depending on volatile component volume lets 3–20% of gases out of the furnace, bypassing the heat exchanger. Each percent of bypassed gases increases heat consumption in the burning process by approx. 20–25 kJ/kg clinker. As a result, the tendency is to limit the size of the bypass. Ecological and economic effects of using alternative fuels makes their production usage grow constantly. This, in turn, results in increased volatile component circulation and the ensuing need to increase the volume of bypassed gases. The article presents one of the ways to reduce thermal losses resulting from operation of a bypass system, involving the use of enthalpy of bypass gases to produce electricity.
7
Content available Ocena metod redukcji emisji NOx na przykładzie procesu wypalania klinkieru cementowego
Duda J., Kazimierczak S., Wasilewski M.
Prace Instytutu Ceramiki i Materiałów Budowlanych
|
2017
|
R. 10, nr 28
7--16
PL
Obecnie jednym z najważniejszych problemów w przemyśle cementowym jest spełnienie wymagań dokumentu BREF z 2013 r. w sprawie limitów emisji NOx w procesie wypalania klinkieru cementowego. Wysokotemperaturowemu, złożonemu procesowi wypalania towarzyszy wysoka emisja NOx. W artykule przedstawiono wyniki badań redukcji NOx z procesu wypalania klinkieru cementowego w piecu obrotowym. Spełnienie warunku emisji NOx poniżej 200 mg/Nm3 wymaga skojarzenia kilku metod redukcji. W związku z tym badania obejmowały zarówno metody pierwotne, jak i wtórne - chemiczne. W pierwszym etapie emisję można ograniczyć poprzez modyfikację procesu technologicznego, a następnie przez zastosowanie metod wtórnych, np. SNCR.
EN
Nowadays, one of the important problems faced by cement industry is meeting requirements of BREF (BAT Reference Document) of 2013 regarding NOx emission limits in clinker burning process. High-temperature burning and complexity of generation of nitrogen oxides are two reasons why this process is accompanied by high emissions of NOx. This paper presents results of broad research on various methods of NOx reduction in rotary kiln, both primary or secondary chemical SNCR or oxidation of NO by hydrogen peroxide aqueous solution. In order to achieve target emission level NOx <200mg/Nm3 it will be necessary to combine few different reduction methods. First, emission shall be reduced by modifying technological process and only after that by the application of secondary methods, e.g. SNCR.
8
Content available Entrepreneurial orientation in high-tech and low-tech SMEs in Malopolska region
Codogni M., Duda J., Kusa R.
Managerial Economics
|
2017
|
Vol. 18, no. 1
7--21
EN
The aim of this paper is to examine the entrepreneurial orientation (EO) of SMEs in the Malopolska region of Poland. Our specific aim is to confirm the relationship between selected company characteristics (the level of technological development and stage of organizational development) and entrepreneurial orientation. A survey was conducted in a group of 95 SMEs that form hightech and low-tech industries in the Malopolska region. Our findings suggest that enterprises representing the high-tech industry exhibit higher EO than those from the low-tech industry. The findings display an imbalance in EO dimensions in both groups of enterprises, showing that innovativeness plays the most important role in enterprises from high-tech industries. The results suggest an inverse monotonic relationship between EO and a company’s age, but they do not confirm any relationship between the EO and a company’s size. Our results contribute to the theory of entrepreneurship by identifying the dependence of EO on industry type (lowtech versus high-tech) and company age.
9
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.
10
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.
11
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.
12
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.
13
Content available A Lyapunov functional for a system with both lumped and distributed delay
Duda J.
Archives of Control Sciences
|
2017
|
Vol. 27, no. 4
527--540
EN
In the paper construction of a Lyapunov functional for time delay system with both lumped and distributed delay is presented. The Lyapunov functional is determined by means of the Lyapunov matrix. The method of determination of the Lyapunov matrix for time delay system with both lumped and distributed delay is presented. It is given the example illustrating the method.
14
Content available Assessment of Utilization of Regions’ Transport Capacity by the DEA Method of Determining Relative Efficiency
Wiśnicki B., Duda J.
Problemy Transportu i Logistyki
|
2016
|
nr 2 (34)
197--207
EN
The paper presents a method of comparison of geographical regions in terms of their transport system efficiency. The method is an alternative to traditional statistical analyses which compare parameters describing the transport capacity and transport performance. It utilizes the opportunities presented by the DEA (Data Envelopment Analysis) in terms of computation of relative technological efficiency. The proposed model provides for quantitative and qualitative verification of particular components of transport systems in the compared geographical regions, and determination of the efficiency frontier. Effectiveness of the method is presented, based on a comparative analysis of Poland’s administrative provinces. An overview of the opportunities provided by the DEA method is outlined together with some methodological recommendations. The conclusions discuss conditions for broader applications of the analysed study method.
PL
Celem artykułu jest przedstawienie metody porównania regionów geograficznych pod względem efektywności ich systemów transportowych. Metoda ta jest alternatywą dla tradycyjnych analiz statystycznych, czyli porównania parametrów opisujących potencjał transportowy i działalność transportową regionów. Wykorzystuje ona możliwości, jakie daje model DEA (Data Envelopment Analysis) w zakresie obliczania względnej efektywności technicznej. Zaproponowany model pozwala na zweryfikowanie ilościowe i jakościowe elementów systemu transportowego porównywanych regionów geograficznych oraz wyznaczanie granicznego poziomu ich wykorzystania. Skuteczność metody zaprezentowano na przykładzie badań porównawczych województw Polski. W syntetyczny sposób pokazano możliwości metody DEA wraz z rekomendacjami metodycznymi. Artykuł kończą autorskie wnioski dotyczące uwarunkowań szerszego zastosowania analizowanej metody badawczej.
15
Content available Numerical simulation of thermal-hydraulic processes in the riser chamber of installation for clinker production
Borsuk G., Dobrowolski B., Nowosielski G., Wydrych J., Duda J.
Archives of Thermodynamics
|
2016
|
Vol. 37, no. 1
127--142
EN
Clinker burning process has a decisive influence on energy consumption and the cost of cement production. A new problem is to use the process of decarbonization of alternative fuels from waste. These issues are particularly important in the introduction of a two-stage combustion of fuel in a rotary kiln without the typical reactor-decarbonizator. This work presents results of numerical studies on thermal-hydraulic phenomena in the riser chamber, which will be designed to burn fuel in the system where combustion air is supplied separately from the clinker cooler. The mathematical model is based on a combination of two methods of motion description: Euler description for the gas phase and Lagrange description for particles. Heat transfer between particles of raw material and gas was added to the numerical calculations. The main aim of the research was finding the correct fractional distribution of particles. For assumed particle distribution on the first stage of work, authors noted that all particles were carried away by the upper outlet to the preheater tower, what is not corresponding to the results of experimental studies. The obtained results of calculations can be the basis for further optimization of the design and operating conditions in the riser chamber with the implementation of the system.
16
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.
17
Content available Lyapunov matrices approach to the parametric optimization of a neutral system
Duda J.
Archives of Control Sciences
|
2016
|
Vol. 26, no. 1
81--93
EN
In the paper a Lyapunov matrices approach to the parametric optimization problem of a neutral system with a P-controller is presented. The value of integral quadratic performance index of quality is equal to the value of Lyapunov functional for the initial function of the neutral system. The Lyapunov functional is determined by means of the Lyapunov matrix.
18
Content available Lyapunov Matrices Approach to the Parametric Optimization of a System with Two Delays
Duda J.
Archives of Control Sciences
|
2016
|
Vol. 26, no. 3
367--381
EN
In the paper a Lyapunov matrices approach to the parametric optimization problem of time-delay systems with two commensurate delays and a P-controller is presented. The value of integral quadratic performance index of quality is equal to the value of the Lyapunov functional for the initial function of time-delay system. The Lyapunov functional is determined by means of the Lyapunov matrix.
19
Technologia CCS w zakładzie cementowym
Duda J., Kołosowski M., Tomasiak J.
Logistyka
|
2015
|
nr 3
1040--1050, CD 1
PL
Na przykładzie przemysłu cementowego przedstawiono problem redukcji emisji dwutlenku węgla. Dotychczasowa działalność sprowadza się głównie do ograniczenia zużycia ciepła w procesie wypalania klinkieru i ograniczenia jego ilości w cemencie. Działania te wyczerpały już praktycznie możliwość dalszej redukcji CO2. Zapowiadane po roku 2020 przez Komisję Europejską nowe, jeszcze większe redukcje wymagają innego podejścia do tego problemu.. W artykule przedstawiono możliwość wykorzystania do tego technologii CCS jako wariantu, który pozwoli uzyskać emisję na wymaganym poziomie.
EN
The issue of carbon dioxide emissions reduction has been presented on the example of cement industry. Existing activities in this area resolve mainly to the reduction of heat consumption in the process of clinker burning and limiting its content in cement. Those activities have almost completely exhausted the possibility of further CO2 reduction. New, even greater reductions, which the European Commission plans to implement after 2020 require a different approach to this problem. The article describes the possibility of using the CCS technology for this purpose, which will allow to obtain the required level of emission.
20
System logistyczny w zakładzie segregacji i przeróbki odpadów
Duda J., Kołosowski M., Tomasiak J.
Logistyka
|
2015
|
nr 3
1030--1039, CD 1
PL
Gospodarka odpadami należy do ważniejszych zadań na poziomie gminy. Wprowadzona w ostatnich latach reforma systemu gospodarki odpadami, zmieniła dotychczasowy sposób zarządzania nimi. Zwiększa ona rolę gminy, która może sama decydować o systemie gospodarowania odpadami na swoim terenie. Wysokie koszty zakładu segregacji i przeróbki odpadów nie pozwalają gminom na zrealizowanie takiej inwestycji. W związku z czym, gospodarka odpadami w gminie ogranicza się najczęściej do tradycyjnego składowania ich na składowisku odpadów. W artykule przedstawiono sposób zagospodarowania odpadów na przykładzie wybranego województwa, polegający na skojarzeniu kilku gmin i stworzeniu wspólnego zakładu segregacji i przeróbki odpadów (ZSPO). Dzięki odpowiedniemu systemowi logistycznemu, można ograniczyć koszty zbiórki i dostarczenia odpadów do zakładu przeróbczego oraz dystrybucji surowców wtórnych i odpadów z ZSPO. Pozwoli to przy niższych kosztach inwestycyjnych i eksploatacyjnych ograniczyć strumień odpadów skierowanych na składowiska i tym samym zwiększyć okres ich wykorzystania.
EN
Waste management is one of the most important tasks at the commune level. The reform of the waste management system established in recent years changed the approach to waste management. It increases the role of the commune, which may itself decide the waste management in its area. High costs of waste sorting and processing plants prevent the communes from making such an investment. Therefore, waste management in communes is usually limited to traditional storage of waste in landfills. The paper describes a method for waste management on the example of a chosen province, based on the association of several communes and setting up a joint waste segregation and processing plant (ZSPO). An appropriate logistic system enables reducing the costs of collection and delivery of waste to a waste processing plant and distribution of recycled materials and waste from ZSPO. It will allow limiting the stream of waste delivered to landfills and at the same time increasing the period of their use with lower investment and exploitation cost.
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