Wyniki wyszukiwania - BazTech

1

Time minimization delivery planning with the time-quantity dependence

Kowalik Przemysław, Stopka Ondrej

Zeszyty Naukowe. Transport / Politechnika Śląska

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2025

|

z. 128

95--114

EN

One of the classical problems in transportation planning is represented minimizing the maximal delivery time of a uniform commodity between sources and destinations, known as the Bottleneck Transportation Problem (BTP). It assumes that a fixed transportation time – independent of the quantity of the transported commodity – is assigned to each source-to-destination route. In some cases, however, the quantity of the transported commodity may affect the transportation time, e.g., because of the duration of loading/unloading the commodity to/from the vehicle. Extensions of the BTP as well as the closely related Total Time Minimization Transportation Problem (TTMTP) which include the linear time-quantity dependence of the delivery time are considered. Whereas similar optimization problems known in the literature are nonlinear, linear programming is used in this research. Linear optimization provides better performance of the optimization software in comparison with nonlinear optimization. The above fact is illustrated by improving solutions to the problems known in the literature. A detailed insight into the issue of the existence of integer optimal solutions and interpretations of optimal solutions is also provided.

2

Optimization of road transport within the supply network - a case study from Poland

Ziółkowski Jarosław, Hošková-Mayerová Sarka, Hutsaylyuk Volodymyr, Łukasiak Daniel

Transport Problems

|

2025

|

T. 20, z. 1

193--206

EN

Optimization in the area of road transport is the subject of numerous scientific publications. Its analysis uses programming languages (including linear) and tools enabling not only a detailed analysis of the examined process but also including data dynamics (demand variability) and the availability of resources (means of transport) diversified in terms of permissible total mass (GVW). Such tools are useful because they support decision-making processes. This paper uses the example of a military supply network to present a multi-criteria methodology enabling minimization of total transport costs, number and type (due to load capacity) of vehicles used, distance traveled, fuel used, and CO2 emissions into the atmosphere. Moreover, additional restrictions on existing transport resources were included, considering the number and type of vehicles available at the base. This is of great importance, especially when there is a need to provide emergency deliveries, for example, in the event of a war threat. The proposed method is universal and was developed using an MS Excel spreadsheet with the Solver add-in.

3

Expert method to support sustainable renovation decisions

Bucoń Robert

Materiały Budowlane

|

2025

|

nr 11

143--151

EN

The purpose of this article is to present a practical application of an expert method for setting renovation priorities for residential building maintenance when setting sustainability goals. The proposed method is based on an innovative approach that provides the techno-economic data necessary to perform a multi-stage optimization to achieve a long-term building renovation strategy. To conduct the study, a mixed-integer linear programming MILP was used that takes into account constraints and boundary conditions that are updated for each year of the time schedule horizon. The developed methodology makes it possible both to identify future renovation activities and to develop a program for their optimal combination, in which the activities are scheduled at the appropriate optimal stage of the time horizon.

PL

W artykule przedstawiono praktyczne zastosowanie eksperckiej metody ustalania decyzji renowacyjnych dotyczących utrzymania budynków mieszkalnych przy wyznaczaniu celów zrównoważonego rozwoju. Proponowana metoda bazuje na nowatorskim podejściu dostarczającym techniczno-ekonomicznych danych niezbędnych do przeprowadzenia wieloetapowej optymalizacji w celu uzyskania długoterminowej strategii renowacji budynków. Do badań zastosowano programowanie liniowe o strukturze mieszanej MILP, uwzględniające ograniczenia i warunki brzegowe, które są aktualizowane w przypadku każdego roku horyzontu czasowego harmonogramu. Opracowana metoda umożliwia zidentyfikowanie przyszłych działań renowacyjnych oraz opracowanie programu optymalnej ich kombinacji, w którym działania te zaplanowane są w odpowiednim optymalnym etapie horyzontu czasowego.

4

Sustainable energy development strategies for Poland – critical

Ligus Magdalena

Economics and Environment

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2025

|

No. 3

art. no. 1306

EN

The aim of the paper and research method is the critical review of the energy development strategies for Poland proposed in strategic government documents, as well as proposals of research institutes. The strategies are confronted with the sustainable development paradigm. Certain conclusions are consistent across all studies: there is no doubt that the future belongs to renewable energy sources. However, the crucial difference concerns whether or not system costs are recognised, or recognised to a different extent, and whether they are assigned to specific energy technologies. Energy strategies presented in the literature are typically based on linear programming, where, subject to certain constraints, only one goal of minimum cost of energy in the power system is achieved. Such a one-dimensional goal definition appears to be a significant simplification of the problem, as costs are only one component of a multidimensional criterion that is the highest level of sustainable energy development.

PL

Celem artykułu jest krytyczny przegląd strategii zrównoważonego rozwoju energetycznego dla Polski, proponowanych w strategicznych dokumentach rządowych oraz propozycjach instytutów badawczych. Strategie te konfrontowane są z paradygmatem zrównoważonego rozwoju. Pewne wnioski są spójne we wszystkich badaniach: nie ma wątpliwości, że przyszłość należy do odnawialnych źródeł energii. Zasadnicza różnica dotyczy jednak tego, czy koszty systemowe są uwzględniane, czy też uwzględniane w różnym stopniu, a także tego, czy są przypisane konkretnym technologiom energetycznym. Strategie energetyczne prezentowane w literaturze opierają się zazwyczaj na programowaniu liniowym, gdzie, przy pewnych ograniczeniach, osiągany jest tylko jeden cel, jakim jest minimalny koszt energii w systemie elektroenergetycznym. Takie jedno-wymiarowe określenie celu wydaje się znacznym uproszczeniem problemu, ponieważ koszty są tylko jednym ze składników wielowymiarowego kryterium, jakim jest najwyższy poziom zrównoważonego rozwoju energetycznego.

5

Optimizing urban transportation network reliability by analyzing road traffic accidents

Pemberthy-R J. Isaac, Gañan-Cardenas Eduard

Archives of Transport

|

2025

|

Vol. 73, iss. 1

155--177

EN

Urbanization has led to increased traffic congestion and road traffic accidents (RTAs), significantly impacting public health, urban mobility, and the efficiency of transportation systems. RTAs disrupt road transport networks, reducing their reliability and performance metrics, which are critical for economic and social activities. This study addresses these challenges by integrating statistical analysis and optimization modeling to enhance the reliability of urban transportation networks through targeted interventions. The proposed methodology builds upon the reliability model by Jovanović Dragan et al. (2011), utilizing statistical analysis of historical RTA data to evaluate transport network reliability. This assessment informs of a linear programming (LP) optimization framework designed to allocate intervention budgets effectively. The LP model incorporates road importance, defined by traffic volume, prioritizing investments on high-impact roads to mitigate RTAs and improve overall network performance. The methodology is demonstrated through a case study in Medellín, Colombia, a city facing significant congestion and high RTA rates (average 100 daily). Using geolocated accident data (2017–2019) and vehicle usage metrics, two model variations were tested: one including road importance and another without. Both models yielded efficient solutions using standard optimization solvers with minimal computational time. Findings demonstrate that the model incorporating road importance provides more targeted budget allocations, aligning better with practical priorities by focusing interventions on the busiest and least reliable road segments. This study highlights the value of combining RTA analysis and network reliability perspectives for data-driven strategic transportation planning. The approach offers actionable insights for policymakers and urban planners seeking to reduce accidents and enhance urban mobility through optimized resource allocation. Future research could expand this framework to include other disruption types (e.g., natural disasters) or validate intervention effectiveness through detailed simulation modeling.

6

Route planning for multiple unmanned aerial vehicles

Aguiar Antônio Lucas Sousa Aguiar, Pinto Vandilberto P., Sousa Lígia Maria Carvalho, Pinheiro José Lucas Da Silva, do Nascimento José Cleilton

Przegląd Elektrotechniczny

|

2024

|

R. 100, nr 9

219--223

EN

This study addresses efficient task assignment for collaborative systems, with a focus on route planning for multiple Unmanned Aerial Vehicles (UAVs). Using the Ant Colony Optimization algorithm and the A* algorithm for obstacle avoidance, the results show that the proposed method allows route planning with acceptable computational time, providing guidance on the optimal number of UAVs in a mission.

PL

Niniejsze badanie dotyczy efektywnego przydzielania zadań dla systemów współpracujących, ze szczególnym uwzględnieniem planowania trasy dla wielu bezzałogowych statków powietrznych (UAV). Wykorzystując algorytm optymalizacji kolonii mrówek i algorytm A* do omijania przeszkód, wyniki pokazują, że proponowana metoda umożliwia planowanie trasy w akceptowalnym czasie obliczeniowym, zapewniając wskazówki dotyczące optymalnej liczby UAV w misji.

7

Assignment of tasks to machines under data replication with a tie to Steiner systems

Wojciechowski Paweł, Kasprzak Marta

International Journal of Applied Mathematics and Computer Science

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2024

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Vol. 34, no. 2

263--275

EN

In the paper a problem of assignment of tasks to machines is formulated and solved, where a criterion of data replication is used and a large size of data imposes additional constraints. This problem is met in practice when dealing with large genomic files or other types of vast data. The necessity of comparing all pairs of files within a big set of DNA sequencing results, which we collected, maintained, and analyzed within a national genomic project, brought us to the proposed results. This problem resembles that of generating a particular Steiner system, and a mechanism observed there is employed in one of our algorithms. Based on the problem complexity, we propose two heuristic algorithms, which work very well even for instances with tight constraints and a heterogeneous environment defined. In addition, we propose a simplified method, nevertheless capable of finding very good solutions and surpassing the algorithms in some special cases. The methods are validated in tests on a wide set of instances, where values of parameters reflect our real-world application and where their usefulness is proven.

8

Modeling environmental and economic factors in regional energy optimization

Coban Hasan Huseyin, Lewicki Wojciech, Brelik Agnieszka

Economics and Environment

|

2024

|

No. 2

art. no. 748

EN

This article addresses the contemporary environmental challenges stemming from rapid economic growth, surging energy consumption, urban expansion, and mounting waste issues. The study explores the optimisation of a regional energy system, considering not only the electric energy sector but also the fuel and thermal energy sectors for the selected geographical destination. In this study, the application of the Linprog optimisation function in MATLAB programming tool to solve Regional Energy System Optimization with renewable resources is explained. The primary objective is to develop a mathematical model that identifies the optimal energy balance structure, allowing for the partial replacement of hydrocarbon sources with bioresources and waste in heat and electricity generation, as well as in vehicle fuel consumption. The modelling approach involves linear programming and integrates two key criteria: economic (cost of energy for consumers) and environmental (carbon footprint). The novelty of this approach lies in applying life cycle analysis to assess potential environmental consequences. Results reveal optimal generation volumes based on economic and environmental considerations. When optimising solely for economic criteria, municipal solid waste, along with wind energy, emerges as the preferred source. In contrast, the simultaneous optimisation of economic and environmental parameters aligns with the economic calculation, demonstrating a balanced approach to sustainable development.

PL

W artykule omówiono współczesne wyzwania środowiskowe wynikające z szybkiego wzrostu gospodarczego, rosnącego zużycia energii, ekspansji miast i narastających problemów z odpadami. W opracowaniu podjęto próbę optymalizacji regionalnego systemu energetycznego, uwzględniając nie tylko sektor energii elektrycznej, ale także sektor paliwowy i energetyki cieplnej dla wybranej lokalizacji geograficznej. W tym opracowaniu wyjaśniono zastosowanie funkcji optymalizacyjnej Linprog w narzędziu programistycznym MATLAB do rozwiązywania problemów z optymalizacją regionalnego systemu energetycznego przy użyciu zasobów odnawialnych. Podstawowym celem jest opracowanie modelu matematycznego identyfikującego optymalną strukturę bilansu energetycznego, pozwalającą na częściowe zastąpienie źródeł węglowodorów biosurowcami i odpadami w procesie wytwarzania ciepła i energii elektrycznej, a także w zużyciu paliwa przez pojazdy. Podejście modelowe obejmuje programowanie liniowe i integruje dwa kluczowe kryteria: ekonomiczne (koszt energii dla konsumentów) i środowiskowe (ślad węglowy). Nowatorstwo tego podejścia polega na zastosowaniu analizy cyklu życia do oceny potencjalnych konsekwencji dla środowiska. Wyniki ujawniają optymalne wielkości produkcji w oparciu o względy ekonomiczne i środowiskowe. W przypadku optymalizacji wyłącznie pod kątem kryteriów ekonomicznych, preferowanym źródłem są stałe odpady komunalne oraz energia wiatrowa. Natomiast jednoczesna optymalizacja parametrów ekonomicznych i środowiskowych pokrywa się z kalkulacją ekonomiczną, wykazując zrównoważone podejście do zrównoważonego rozwoju.

9

An Improved Genetic Algorithm for Set Cover using Rosenthal Potential

Tayebi Dena, Ray Saurabh, Ajwani Deepak

Annals of Computer Science and Information Systems

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2024

|

Vol. 39

689--694

EN

A major issue with heuristics for set-cover problem is that they tend to get stuck in a local optimum typically because a large local move is necessary to find a better solution. A recent theoretical result shows that replacing the objective function by a proxy (which happens to be Rosenthal potential function) allows escaping such local optima even with small local moves albeit at the cost of an approximation factor. The Rosenthal potential function thus has the effect of smoothing the optimization landscape appropriately so that local search works. In this paper, we use this theoretical insight to design a simple but robust genetic algorithm for weighted set cover. We modify the fitness function as well as the crossover operator of the genetic algorithm to leverage the Rosenthal potential function. We show empirically this greatly improves the quality of the solutions obtained especially in examples where large local moves are required. Our results are better than existing state of the art genetic algorithms and also comparable in performance with the recent local search algorithm NuSC (carefully engineered for set cover) on benchmark instances. Our algorithm, however, performs better than NuSC on simple synthetic instances where starting from an initial solution, large local moves are necessary to find a solution that is close to optimal. For such instances, our algorithm is able to find near optimal solutions whereas NuSC either takes a very long time or returns a much worse solution.

10

A new geometric approach to multiobjective linear programming problems

Kaci Mustapha, Radjef Sonia

Mathematica Applicanda

|

2023

|

Vol. 51, no. 1

3--12

EN

This paper is a follow-up to a previous work where we developed a new geometric approach to sensitivity analysis. In this paper, we present a simple method to determine whether a given multiobjective linear programming problem (MOLPP) has an ideal solution (i.e. all of the objective functions are optimized simultaneously) without having to calculate the optimal value of each objective function. First, we divide the space of linear forms into a finite number of sets based on a fixed convex polygonal subset of R2 using an equivalency relationship. All the elements from a given equivalency class have the same optimal solution. Next, we characterize the equivalence classes of the quotient set using a geometric approach to sensitivity analysis. Finally, a numerical example is given to illustrate the method.

PL

W tym artykule przedstawiamy nową metodę rozwiązywania problemów programowania liniowego z wieloma celami (MOLPP), która eliminuje potrzebę obliczania optymalnej wartości każdej funkcji celu. Metoda ta jest kontynuacją naszych wcześniejszych prac dotyczących analizy wrażliwości, gdzie opracowaliśmy nowe podejście geometryczne. Pierwszym krokiem naszego podejścia jest podział przestrzeni form liniowych na skończoną liczbę zbiorów opartych na stałym wypukłym podzbiorze wielokąta R2. Dokonujemy tego za pomocą relacji równoważności, która zapewnia, że wszystkie elementy z danej klasy równoważności mają takie same rozwiązanie optymalne. Następnie charakteryzujemy klasy równoważności zbioru ilorazowego za pomocą podejścia geometrycznego do analizy wrażliwości. Ten krok jest kluczowy w identyfikacji rozwiązania idealnego dla MOLPP. Korzystając z tego podejścia, możemy określić, czy dana MOLPP ma rozwiązanie idealne, bez konieczności obliczania optymalnej wartości każdej funkcji celu. Jest to znacząca poprawa w stosunku do istniejących metod, ponieważ znacznie zmniejsza złożoność obliczeniową i czas wymagany do rozwiązania MOLPP. Aby zilustrować naszą metodę, przedstawiamy numeryczny przykład, który dowodzi jej skuteczności. Nasza metoda jest prosta, ale potężna i może być łatwo zastosowana do szerokiego zakresu MOLPP. Niniejsza praca przyczynia się do dziedziny optymalizacji poprzez przedstawienie nowego podejścia do rozwiązywania MOLPP, które jest wydajne, skuteczne i łatwe do zaimplementowania.

11

List Of Pareto Optimal Solutions of a Biobjective Shortest Path Problem

Laskov Lasko, Marinov Marin

Annals of Computer Science and Information Systems

|

2023

|

Vol. 35

603--613

EN

Many applications in practice involve the search for a shortest path in a network by optimizing two conflicting objective functions. Such problems often are referred to as biobjective optimization problems. Their goal is to find special optimal paths that are nondominated and are also known in the specialized literature as to as Pareto optimal. While most of the existing methods aim to find the minimum complete set of Pareto optimal paths, we propose an approach that is able to generate a list of all Pareto optimal solutions in a given network.

12

Efficient exact A* algorithm for the single plant Hydro Unit Commitment problem

Heintzmann Alexandre, Artigues Christian, Bendotti Pascale, Ngueveu Sandra Ulrich, Rottner Cécile

Annals of Computer Science and Information Systems

|

2023

|

Vol. 35

533--543

EN

The Hydro Unit Commitment problem (HUC) specific to hydroelectric plants is part of the electricity production planning problem, called Unit Commitment Problem (UCP). More specifically, the studied case is that of the HUC with a single plant, denoted 1-HUC. The plant is located between two reservoirs. The horizon is discretized in time periods. The plant operates at a finite number of points defined as pairs of the generated power and the corresponding water flow. Several constraints are considered. Each reservoir has an initial volume, as well as window resource constraints, defined by a minimum and maximum volume per time period. At each time period, there is an additional positive, negative or zero intake of water in the reservoirs. The case of a price-taker revenue maximization problem is considered. An efficient exact A* variant, so called HA*, is proposed to solve the 1-HUC accounting for window constraints, with a reduced search space and a dedicated optimistic heuristic. This variant is compared to a classical Resource Constrained Shortest Path Problem (RCSPP) algorithm and a Mixed Integer Linear Programming formulation solved with CPLEX. Results show that the proposed algorithm outperforms both concurrent alternatives in terms of computational time in average on a set of realistic instances, meaning that HA* exhibits a more stable behavior with a larger number of instances solved.

13

Independent component analysis based on Jacobi iterative framework and L1-norm criterion

Borowicz Adam

Annals of Computer Science and Information Systems

|

2022

|

Vol. 30

305--312

EN

Most recently, a link between principal component analysis (PCA) based on L1-norm and independent component analysis (ICA) has been discovered. It was shown that the ICA can actually be performed by L1-PCA under the whitening assumption, inheriting the improved robustness to outliers. In this paper, a novel ICA algorithm based on Jacobi iterative framework is proposed that utilizes the non-differentiable L1-norm criterion as an objective function. We show that such function can be optimized by sequentially applying Jacobi rotations to the whitened data, wherein optimal rotation angles are found using an exhaustive search method. The experiments show that the proposed method provides a superior convergence as compared to FastICA variants. It also outperforms existing methods in terms of source extraction performance for Laplacian distributed sources. Although the proposed approach exploits the exhaustive search method, it offers a lower computational complexity than that of the optimal L1-PCA algorithm.

14

Optymalizacja kosztów transportu gazu skroplonego LNG pod względem lokalizacji magazynów na przykładzie Polski

Popławski Tomasz, Kurkowski Bartosz

Rynek Energii

|

2021

|

Nr 4

3--8

PL

Wielu ekspertów zarówno z Polski jak i UE jednoznacznie stwierdza, że Gazociąg Nordstream 2 zmniejsza bezpieczeństwo gazowe zarówno Polski jaki i państw z Europy środkowowschodniej. W związku z tym konieczne są różne przedsięwzięcia w celu dywersyfikacji dostaw gazu do Polski. Przy istniejącej i wciąż rozwijającej się infrastrukturze drogowej oraz kolejowej, jak również w obliczu istnienia terminali do odbioru gazu w Świnoujściu i Gdańsku, jednym z możliwych działań w tym kierunku jest budowa nowych magazynów lub rozbudowa starych w taki sposób, aby można było przewozić i przechowywać tam skroplony gaz LNG. Jednak, aby przedsięwzięcie to było opłacalne, lokalizacje tych magazynów muszą tak zostać dobrane, aby zminimalizować przyszłe koszty transportowe. W niniejszym artykule zaproponowano metodę opartą o programowanie liniowe, która pozwala na optymalną alokację magazynów LNG. Jej innowacyjnym względem istniejących metod elementem jest dynamicznie aktualizująca się waga dostawcy, w zależności od przypisanych do niego odbiorców. Dla zaprezentowanego przykładu zaproponowana metoda pozwoliła na zmniejszenie kosztów drogowych o ponad 25%.

EN

Many experts from both Poland and the EU clearly state that the Nordstream 2 gas pipeline reduces gas safety both in Poland and in Central and Eastern European countries. With the existing and still developing road and rail infrastructure, as well as the gas receiving terminals in Świnoujście and Gdańsk, one of the possible actions is the construction of new warehouses or expansion of old ones so that LNG can be transported and stored there. However, for this venture to be profitable, the locations of these warehouses must be selected to minimize future transport costs. This article proposes a method based on linear programming that allows for the optimal allocation of LNG storage facilities. Its innovative element compared to the existing methods is the dynamically updating weight of the supplier, depending on the recipients assigned to it. For the example shown, the proposed method allowed to reduce road costs by more than 25%.

15

Comparative Study of AMPL, Pyomo and JuMP Optimization Modeling Languages on a Network Linear Programming Problem Example

Karbowski Andrzej, Wyskiel Krzysztof

Pomiary Automatyka Robotyka

|

2021

|

R. 25, nr 3

23--30

EN

The purpose of this work is a comparative study of three languages (environments) of optimization modeling: AMPL, Pyomo and JuMP. The comparison will be based on three implementations of the shortest path problem formulated as a linear programming problem. The codes for individual models and differences between them will be presented and discussed. Various aspects will be taken into account, such as: simplicity and intuitiveness of implementation, availability of specific data structures for a LP network problems, etc.

PL

Celem pracy jest zbadanie i porównanie możliwości trzech języków (środowisk) modelowania optymalizacyjnego: AMPL, Pyomo i JuMP. Porównanie zostanie oparte na trzech implementacjach zadania najkrótszej ścieżki sformułowanego jako zadanie programowania liniowego. Przedstawione i omówione zostaną kody poszczególnych modeli oraz różnice między nimi. Pod uwagę będą brane różne aspekty, takie jak: prostota i intuicyjność implementacji, dostępność określonych struktur danych dla problemów z siecią LP itp.

16

A new geometric approach for sensitivity analysis in linear programming

Kaci Mustapha, Radjef Sonia

Mathematica Applicanda

|

2021

|

Vol. 49, no. 2

145--157

EN

The article presents a geometric method of sensitivity analysis in linear programming, which is a computationally practical way to study the behavior of an optimal solution to a linear programming problem. In this approach, we improve the implementation of the constraints, and then we formulate the problem of linear programming geometrically. In this way, we obtain a new, equivalent geometrical formulation of the problem for the sensitivity analysis using the concepts of affine geometry. It consists in entering the objective function coefficient vector in the polar coordinates and determining all angles for which the solution remains unchanged. The method is presented in detail and illustrated by a numerical example.

PL

W niniejszym artykule przedstawiamy nowe podejście geometryczne do analizy wrażliwości w programowaniu liniowym, które jest praktyczne obliczeniowo. Pozwala analizować zachowania optymalnego rozwi¡zania problemu programowania liniowego przy zmianach danych zadania. Najpierw ustalamy dopuszczalną dziedzinę (naprawiamy ograniczenia liniowe). Następnie geometrycznie formułujemy problem programowania liniowego. Nast¦pnie podajemy nowe równoważne sformułowanie geometryczne problemu analizy wrażliwości przy użyciu pojęć geometrii afinicznej. Piszemy wektor współczynników funkcji celu we współrzędnych biegunowych i wyznaczamy wszystkie kąty, dla których rozwiązanie pozostaje niezmienione. Proponowane podejście zostało szczegółowo przedstawione i zilustrowane przykładem liczbowym.

17

An example to illustrate several aspects of optimization theory in Managerial Economics

Lahiri Somdeb

Managerial Economics

|

2021

|

Vol. 22, no. 1

23--34

EN

We provide a single example that illustrates all aspects of linear, integer and dynamic programming, including such concepts such as value of perfect and imperfect information. Such problems, though extremely plausible and realistic are hardly ever discussed in managerial economics.

18

Optimum transportation of relief materials aftermath the disaster

Nautiyal A., Kumar A., Poddar A., Parajuli N.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

|

Vol. 109, nr 1

26--41

EN

Purpose: Natural disasters disrupt not only the lives of individuals but also the functioning of society. Given the unpredictability of disasters and the uncertainty associated with them, preparation is the best way to mitigate and reduce the effects of the disaster. Design/methodology/approach: The study presents a mathematical model in the form of a multi-objective linear programming problem for the relief distribution from the airports which minimizes the total operational cost as well as travel time. Further, the solution approach and analytical results have also been discussed. Findings: The main aims at the preparedness stage are to identify and build infrastructures that might function as useful operation centres during a disaster. The study also provides decisions that include the type and number of vehicles for each affected location. Research limitations/implications: Airports can function as centres for relief collection and distribution. However, relief operations carried out through airports are often subject to problems such as stockpiling. Further, various modes are available for the transport of relief supplies- air, water, and land transport modes primarily. While aircraft and helicopters are faster, their costs of operation are too high. Instead, trucks are economical but very slow as compared to aircraft. Practical implications: The choice of model depends on many factors including the availability of vehicles, availability of routes, and criticality of situations. The choices made in turn affect the costs and the time of operations. Originality/value: The model converts a disaster scenario into a demand-supply problem with the aim being to decide allocations at specified intervals of time.

19

Conditions and a computation method of the constrained regulation problem for a class of fractional-order nonlinear continuous-time systems

Si Xindong, Yang Hongli, Ivanov Ivan G.

International Journal of Applied Mathematics and Computer Science

|

2021

|

Vol. 31, no. 1

17--28

EN

The constrained regulation problem (CRP) for fractional-order nonlinear continuous-time systems is investigated. New existence conditions of a linear feedback control law for a class of fractional-order nonlinear continuous-time systems under constraints are proposed. A computation method for solving the CRP for fractional-order nonlinear systems is also presented. Using the comparison principle and positively invariant set theory, conditions guaranteeing positive invariance of a polyhedron for fractional-order nonlinear systems are established. A linear feedback controller model and the corresponding algorithm of the CRP for fractional nonlinear systems are also proposed by using the obtained conditions. The presented model of the CRP is formulated as a linear programming problem, which can be easily implemented from a computational point of view. Numerical examples illustrate the proposed method.

20

Risk management in the process of personnel allocation to jobs

Krynke Marek

System Safety : Human - Technical Facility - Environment

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2020

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Vol. 2, nr 1

82--99

EN

The strategy should be designed in such a way as the risk management can operate not only as a system for avoiding losses, but also risk management should allow recognizing and making use of occasions and create new opportunities for the organization. Risk management includes both an evaluation (analytical and evaluation) undertaking as well as planning and control activities aimed at minimizing (reducing) risk or maintaining it at an acceptable level. Security management can in particular be reduced to the issue of risk management, because risk is a quantitative expression of the functioning of systems in an environment where there are active sources of threats to system security. The article presents the problem of personnel allocation in hazardous conditions, emphasizing the possibilities of undertaking optimization actions in the safety management process. A mathematical model was formulated for this issue. An algorithm solving the problem of personnel allocation is presented. The proposed analysis is the starting point for determining the risk when using multi-station work.