Browsing by Subject "scheduling"

Now showing 1 - 20 of 31

Access status: Open Access ,
A method for scheduling the goods receiving process in warehouse facilities
(AGH University of Science and Technology Press, 2008) Ambroziak, Tomasz; Lewczuk, Konrad
The paper discusses the role of goods receiving/shipping scheduling in the warehousing process design. A formal notation of schedules is proposed and implemented in a software application for a specific analytical example.
Access status: Open Access ,
Analiza porównawcza trzech metod planowania produkcji dla systemów przepływowych bez magazynów
(Wydawnictwa AGH, 2007) Magiera, Marek
The three methods of production planning for multistage systems without intermediate buffers are presented. The two methods are hierarchical and the one is monolithic. The methods are constructed for machine loading and task scheduling. The mathematical linear models are constructed for the methods. The time criterion is used in the mixed integer programming. Results of computational experiments with the proposed approaches for production planning are presented. The maximum workloads and CPU run times are compared for all methods.
Access status: Open Access ,
Batch scheduling of deteriorating products
(2007) Barketau, Maksim S.; Cheng, T. C. Edwin; Kovalëv, Mihail Y.; Ng, C. T. Daniel
In this paper we consider the problem of scheduling $N$ jobs on a single machine, where the jobs are processed in batches and the processing time of each job is a simple linear increasing function depending on job's waiting time, which is the time between the start of the processing of the batch to which the job belongs and the start of the processing of the job. Each batch starts from the setup time $S$. Jobs which are assigned to the batch are being prepared for the processing during time $S_{0} < S$. After this preparation they are ready to be processed one by one. The non-negative number $b_i$ is associated with job $i$. The processing time of the $i$-th job is equal to $b_{i}(s_{i} - (s_{i}^{b} + S0))$, where $s_{i}^{b}$ and $s_i$ are the starting time of the $b$-th batch to which the $i$-th job belongs and the starting time of this job, respectively. The objective is to minimize the completion time of the last job. We show that the problem is NP-hard. After that we present an $O(N)$ time algorithm solving the problem optimally for the case $b_{i} = b$. We further present an $O(N^{2})$ time approximation algorithm with a performance guarantee 2.
Access status: Open Access ,
Bloki w problemie przepływowym z minimalizacją sumy kosztów opóźnień
(Wydawnictwa AGH, 2007) Bożejko, Wojciech; Grabowski, Józef; Wodecki, Mieczysław
Blocks are applied in the best metaheuristic algorithms of solving flow shop problem with the makespan ($C_{max}$) criterion. It makes possible to eliminate moves which generates worse elements of a neighborhood. In this paper we present generalization of the classic block formulation, which we are applying in the tabu search algorithm to solving total tardiness flow shop problem $(F||\Sigma w_{i}T_{i})$.
Access status: Restricted ,
Container placement strategies for NFV application in heterogeneous environments
(Data obrony: 2019-10-25) Szmit, Bartosz; Kawałek, Michał
Wydział Informatyki, Elektroniki i Telekomunikacji
Access status: Restricted ,
Container placement strategies for NFV application in heterogeneous environments
(Data obrony: 2019-10-25) Kawałek, Michał; Szmit, Bartosz
Wydział Informatyki, Elektroniki i Telekomunikacji
Access status: Open Access ,
CP-driven production process planning in multiproject environment
(2008) Banaszak, Zbigniew; Bocewicz, Grzegorz; Bach, Irena
The way enterprise capabilities are used decides about its competitiveness among other ones. In that context modeling aimed at production tasks allocation planning plays a crucial role especially at concurrently executed production orders. The introduced reference model employing constraint programming (CP) paradigm describes both an enterprise and a set of project-like production orders. Moreover, encompassing consumer orders requirements and available production capabilities, the model provides the formal framework allowing one to develop a class of decision support systems aimed at interactive production process planning subject to multiproject environment constraints. In that context our contribution is a knowledge-based and CP-driven approach to resource allocation assuming precise character of decision variables. The conditions sufficient for deadlock avoidance are the main goal. The conditions delivered provide formal framework for developing a task oriented Decision Support Tool for Project Portfolio Prototyping (DST4P, Banaszak 2006). The tool provides a prompt and interactive service to a set of routine queries formulated either in straight or reverse way.
Access status: Open Access ,
h-Relation personalized communication strategy
(Wydawnictwa AGH, 2010) Paszyński, Maciej
This paper considers the communication patterns arising from the partition of geometrical domain into sub-domains, when data is exchanged between processors assigned to adjacent sub-domains. It presents the algorithm constructing bipartite graphs covering the graph representation of the partitioned domain, as well as the scheduling algorithm utilizing the coloring of the bipartite graphs. Specifically, when the communication pattern arises from the partition of a 2D geometric area, the planar graph representation of the domain is partitioned into not more than two bipartite graphs and a third graph with maximum vertex valency 2, by means of the presented algorithm. In the general case, the algorithm finds h - 1 or fewer bipartite graphs, where h is the maximum number of neighbors. Finally, the task of message scheduling is reduced to a set of independent scheduling problems over the bipartite graphs. The algorithms are supported by a theoretical discussion on their correctness and efficiency.
Access status: Open Access ,
Integrated scheduling in a supply chain by mixed integer programming
(AGH University of Science and Technology Press, 2008) Sawik, Tadeusz
A mixed integer programming approach is proposed for a long-term, integrated scheduling of material manufacturing, material supply and product assembly in a customer driven supply chain. The supply chain consists of three distinct stages: manufacturer/ supplier of product-specific materials (parts), producer where finished products are assembled according to customer orders and a set of customers which generates final demand for the products. The overall problem is how to coordinate manufacturing and supply of parts and assembly of products so that the total supply chain inventory holding cost and the production line start-up and parts shipping costs are minimised. Numerical examples are presented and some computational results are reported.
Access status: Open Access ,
Methodology for cost oriented assembly line balancing problems
(AGH University of Science and Technology Press, 2011) Grzechca, Waldemar
Assembly lines are special flow-lines production systems which are typical in the industrial production of high quantity standardized commodities. Assembly line balancing is based on evenly distribution of operations between workstations so that each idle time of the machines was minimal. It is assumed that operation times on the machines and the precedence relationship existing between the operations which results from the technology of the production line and the cycle time or the number of machines are known. In the paper short description about general assembly line problem and cost-oriented is described. Next the author presents description of used algorithms. A numerical example is calculated and the results are discussed. Presented paper shows that cost oriented assembly line balancing problem differs from time oriented problem and the differences are underlined.
Access status: Open Access ,
Metoda analizy minimów lokalnych w rozwiązywaniu pewnych problemów optymalizacji dyskretnej
(Wydawnictwa AGH, 2009) Bożejko, Wojciech; Wodecki, Mieczysław
In this paper we consider two machine flow shop problem with penalties sum minimization criterion where penalties are established for jobs tardiness. We propose an approximate algorithm which the main element is a module of local minima analyzing determining by a fast local search algorithm. We compare the obtained results with the optimal solutions.
Access status: Open Access ,
Metoda selekcji dostawców i środków transportu dla sieci dostaw
(Wydawnictwa AGH, 2011) Magiera, Marek
Do ogniw sieci dostaw, dla której zbudowano wielopoziomową metodę, należą m. in. producenci: części składowych, złożonych wyrobów. Na pierwszym poziomie metody ma miejsce wybór dostawców - producentów części składowych. Drugi poziom metody poświęcono wyborze firm transportowych i przynależnych im środków transportu. Dla każdego z poziomów metody zbudowano liniowe modele zadań programowania całkowitoliczbowego, w których uwzględniono kryteria kosztowe. Zamieszczono wyniki eksperymentów obliczeniowych.
Access status: Open Access ,
Metody harmonogramowania procesów w systemach operacyjnych czasu rzeczywistego
(Wydawnictwa AGH, 2009) Szymczyk, Piotr; Szymczyk, Magdalena
Scheduling in RTOS have direct influence on performance of whole system, so selection of the right algorithm is very important part of the configuration. The number of scheduling methods exists. This paper is a survey of scheduling algorithms for real time operating systems.
Access status: Restricted ,
Metody kombinatoryczne wykorzystywane do tworzenia harmonogramów sportowych
(Data obrony: 2012-10-22) Tomala, Magdalena
Wydział Matematyki Stosowanej
Access status: Open Access ,
Modelowanie przepływu zadań w elastycznym systemie produkcyjnym z wózkami AGV
(Wydawnictwa AGH, 2005) Smutnicki, Czesław; Tyński, Adam
W pracy rozważa się system produkcyjny o strukturze przepływowej (szeregowej), w którym maszyny zorganizowane są w układ typu pętla, zaś do transportu zadań pomiędzy maszynami wykorzystuje się pojedynczy, jednokierunkowy wózek AGV. Jako kryterium optymalizacji przyjmuje się moment zakończenia wykonywania zadań procesu technologicznego. Dla problemu przedstawia się model matematyczny oraz wprowadza się model permutacyjno-grafowy, oba poparte wyczerpującym przykładem obliczeniowym.
Access status: Open Access ,
Modułowy system wspomagania zarządzaniem łańcuchem dostaw
(Wydawnictwa AGH, 2009) Magiera, Marek
The paper presents the three-level method of supporting supply chain management. The initial schedule for each manufacturer is created at the first level. The second level is used for scheduling of transport products between manufactures. The final schedule for each manufacturer is created at the third level. The linear mathematical models of mixed integer programming are used in the method. The global optimization (minimization of costs) and local optimization (for each manufacture) are simultaneously regarded in the described method.
Access status: Open Access ,
Neighbourhood properties in some single processor scheduling problem with variable efficiency and additional resources
(2011) Gorczyca, Mateusz; Janiak, Adam; Janiak, Władysław
In the paper, we consider a problem of scheduling a set of tasks on a single processor. Each task must be preprocessed before it can be started on a processor. The efficiency of preprocessing is variable, i.e., the rate of the task preprocessing depends on the amount of continuously divisible resource allotted to this task. This dependency is given by concave, continuous, non-negative and strictly increasing function of the resource amount. The total consumption of resource at each moment is upper bounded. The objective is to minimize the maximum task completion time. The considered problem is NP-hard. Such a problem appears, e.g., in steel mill systems, where ingots (before hot rolling on the blooming mill) have to achieve the required temperature in the preheating process in soaking pits. Some new properties of the problem are proved. These properties are used to construct the procedure for evaluation of the neighbourhood. The procedure is proposed to improve the efficiency of algorithms based on the neighbourhood concept, such as metaheuristics. The computational experiment is conducted to examine the efficiency of the proposed procedure. The described approach can be easily used in the other discrete-continuous scheduling problems.
Access status: Open Access ,
Nowe własności harmonogramów cyklicznych w systemie przepływowym
(Wydawnictwa AGH, 2007) Smutnicki, Czesław; Smutnicki, Adam
This paper deals with the deterministic variant of the problem of optimization cycle run in flow shop repetitive manufacturing system with no store constraints. Starting from earlier papers of the author on this subject, in this paper there are presented some, also new, properties with unpublished yet proofs, efficient algorithms of finding schedule for fixed order of processing tasks in the cycle as well as some experimental results.
Access status: Open Access ,
Optymalizacja struktury procesów rynkowych
(Wydawnictwa AGH, 2009) Kaleta, Mariusz; Smolira, Kamil; Toczyłowski, Eugeniusz
The proposition of multi-criteria mixed-integer optimization model for various market processes' structure is discussed. First we present general formulation of the model and next we consider the possibilities of convenient model adaptation to the specific market systems. We also analyze the possibilities of modelling market developer's preferences using the reference point method. All detailed issues are presented using a power market example.
Access status: Open Access ,
Resource management in machine scheduling problems a survey
(2007) Janiak, Adam; Janiak, Władysław; Lichtenstein, Maciej
The paper is a survey devoted to job scheduling problems with resource allocation. We present the results available in the scientific literature for commonly used models of job processing times and job release dates, i.e., the models in which the job processing time or the job release date is given as a linear or convex function dependent on the amount of the additional resource allotted to the job. The scheduling models with resource dependent processing times or resource dependent release dates extend the classical scheduling models to reflect more precisely scheduling problems that appear in real life. Thus, in this paper we present the computational complexity results and solution algorithms that have been developed for this kind of problems.