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1

Generalized Benders Decomposition to solve a nonlinear routing problem with queueing delay goal function

Kozerski Kacper, Karbowski Andrzej

International Journal of Electronics and Telecommunications

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2025

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Vol. 71, No. 4

34

EN

We address the multicommodity flow problem with a nonlinear goal function modeling queueing delay. It is well-known that linear programming solvers perform better than those used for nonlinear programming. We can leverage their performance by employing the Generalized Benders Decomposition (GBD) to partition the problem into master and primal subproblems. We prove that in the case of multiple subproblems, which is true in our case, we can split both the optimality and feasibility cuts and add them independently. Moreover, we extended a known proof of convergence to enable a wider range of problems to be solved using GBD. We use the split cuts technique to precompute feasibility cuts and analytically solve the subproblems to omit the use of nonlinear optimization software. Furthermore, we explore the possibilities of starting point selection through linear and quadratic approximation. We carry out tests on a classical network example to show that GBD can sometimes outperform nonlinear solvers, and also that quadratic approximation for starting point selection can provide strictly better solution times, dominating commercial solvers.

2

Improving the methodology for optimizing multimodal transportation delivery routes and cyclic schedules in a transnational direction

Taran Igor, Bikhimova Guldana, Danchuk Victor, Toktamyssova Aliya, Tursymbekova Zakira, Oliskevych Myroslav

Transport Problems

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2024

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T. 19, z. 1

157--170

EN

This study considers the task of planning the routes of multimodal transnational cargo transportation. Due to the extremely long length of such routes, delivery times and costs per cargo unit are extremely important. Delays in various types of transport and in the case of cargo transshipment are associated not only with the growth of cargo flows but also with the inconsistency of vehicle schedules. The purpose of this study is to improve the previously developed methodology for optimizing multimodal cargo transportation, taking into account the need for its application to transnational transport corridors. The content of the formulated network problem is reduced to a modification of the traveling salesman problem with an unknown number of transport points the route should pass through. Such a problem is NP-hard due to the time complexity of the algorithms. A modified algorithm has been developed, according to which the general problem with the number of N points is divided into several subproblems. Transport points are grouped into consecutive subsets that are related by only one non-alternative way of transportation. This way can be any “bottleneck” of the transport network or an artificially created one. Such a decomposition of the problem gives a set of partial solutions, which were combined into the final optimal solution. The obtained solution to the routing problem of multimodal routes takes into account the cyclical schedules of the transport operation and gives a guaranteed exact optimum for calculations performed within the permissible time. In addition to determining the optimal route, the algorithm makes it possible to determine the required number of vehicles and their work schedules depending on the total cargo flow on the route.

3

In-vitro Digestibility Organic Materials – Relation with Field Mass Loss Litter Bag Method

Sousa João Ricardo, Singh Abhishek, Ghazaryan Karen, Singh Rupesh Kumar, Trindade Henrique, Coutinho João

Journal of Ecological Engineering

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2024

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Vol. 25, nr 8

253--263

EN

Decomposition and litterfall are the primary mechanisms by which plants release their organic matter and nutrients into the soil, which helps prepare the stage for beneficial pathways in the restoration of damaged ecosystems. Species selection and allocation for the successful use of litter in ecological agricultural fields relies on knowing the mechanisms of plant litter decomposition and its influence on soil nutrients, which are crucial aspects of the ecosystem material cycle. In current study, in-vitro dry matter digestibility (IVDMD) used for evaluating quality animal feed reveals some potential in the decomposition of organic matter estimated. Nevertheless, some consensual advantages as laboratory incubation, this methodology demands a validation procedure. Therefore, the present work aimed to validate the IVDMD methodology by comparison with field buried litter bag mass loss, for 27 organic materials with different origins and chemical quality. The results reveal significant differences among the organic materials studied, reflecting their chemical quality variation, with digestibility values varying between 10.1g·kg-1 in composted sewage sludge and 982.0 g·kg-1 in pig meat meal. IVDMD presented high accuracy results for all studied periods, with best results observed for 28 days incubation period (r2adj=0.959***). Taking the chemical fractions that participated in initial decomposition process the IVDMD is a potential indicator of a labile decomposable pool of organic materials. Considering the high accuracy, repeatability (CV=4.6%) and practicability, the IVDMD is a reliable alternative to the litter bag method in field mass loss availability.

4

Kinetic Model for the Decomposition Rate of the Binder in a Foundry Sand Application

Matsushita Taishi, Sundaram Dinesh, Belov Ilja, Dioszegi Attila

Archives of Foundry Engineering

|

2024

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Vol. 24, iss. 3

43--49

EN

Accurate kinetic parameters are vital for quantifying the effect of binder decomposition on the complex phenomena occurring during the casting process. Commercial casting simulation tools often use simplified kinetic parameters that do not comprise the complex multiple reactions and their effect on gas generation in the sand core. The present work uses experimental thermal analysis techniques such as Thermogravimetry (TG) and Differential thermal analysis (DTA) to determine the kinetic parameters via approximating the entire reaction during the decomposition by multiple first-order apparent reactions. The TG and DTA results reveal a multi-stage and exothermic decomposition process in the binder degradation. The pressure build-up in cores/molds when using the obtained multi-reaction kinetic model is compared with the earlier approach of using an average model. The results indicate that pressure in the mold/core with the multi-reaction approach is estimated to be significantly higher. These results underscore the importance of precise kinetic parameters for simulating binder decomposition in casting processes.

5

Analysis of the fractional descriptor linear systems by the decomposition into the dynamical and static parts

Kaczorek Tadeusz, Sajewski Lukasz

Archives of Control Sciences

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2024

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Vol. 34, No. 4

743--753

EN

A new method of the decomposition of the fractional descriptor linear continuoustime and discrete-time systems into dynamical and static parts is proposed. Conditions for the decomposition of the fractional descriptor linear systems are established and procedures for compositions of the matrices of dynamical and static parts are given. The procedures are illustrated by numerical examples.

6

Efficiency multi-agent model assisted Moea/D algorithm for optimization design for building taking into account annual energy consumption and annual user discomfort hours

Deng Hua, Zhou Kai

Archives of Civil Engineering

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2024

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Vol. 70, nr 4

477--489

EN

Recently, with the continuous consumption of energy, building energy conservation has been popular in the energy field. In response to the high computational cost, slow convergence speed, and low accuracy of existing optimization design methods for building energy efficiency, this study first built a multi-objective optimization model for building energy efficiency on the ground of the annual energy consumption of buildings and the quantity of uncomfortable hours for users. Then it introduces a multi-agent model auxiliary mechanism to improve the decomposition based multi-objective evolutionary optimization algorithm, and then solves the multi-objective optimization model for building energy efficiency. In order to select the optimal decision variable of the algorithm, the decision parameters were analyzed and found that the performance was optimal when the number of samples, aggregation number and base model were set to 25.3 and 20. The improved multi-objective evolutionary optimization algorithm on the ground of decomposition has average supervolume and running time values of 32416.13 and 1774.58 seconds under office buildings, and 7899.13 and 3616.96 seconds under residential buildings, respectively. In addition, the annual user discomfort time of office buildings is 555.28h, which is lower than other comparison algorithms. In summary, the optimal performance of the algorithm when the decision variable is set to 25.3 and 20. The algorithm proposed by the research institute has superior performance and has certain application value in selecting the optimal solution for building energy-saving design.

7

Efficient and robust medical image watermarking based on optimal subband tree structuring and discrete fractional fourier transform

Chacko Anusha, Chacko Shanty

Computer Assisted Methods in Engineering and Science

|

2023

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Vol. 30, no. 4

557--581

EN

In order to solve the security problems associated with medical information and improve the robustness of watermarking algorithms for medical images, a unique approach to watermarking based on block operations is presented. This study considers the medical images as the cover image, with the watermark logo considered secret information that needs to be protected over the wireless transmission in telemedicine. In the embedding phase, input with the discrete fractional Fourier transform is first applied to the input, and then level 2 wavelet decomposition is carried out to determine the optimal sub-band tree. For each tree node on level 2, the approximated and detailed coefficient is determined through the feature analysis perspective. The novelty of the adopted methodology is its simplified transformation and embedding process. Upon receiving a complex matrix, it separates the real part from imaginary part where block transformation is carried out for embedding the watermark pixels. In the extraction phase, just a reverse operation is performed. The watermarking evaluation is performed by simulating various image processing attacks on watermarked medical images. The simulation outcome demonstrates the effectiveness of that proposed watermarking scheme against various attacks. The proposed watermarking technique is robust under various attacks based on image statistics such as PSNR, BER, and the correlation coefficient.

8

Shuffle algorithm for fractional descriptor Roesser type continuous-time linear systems

Kaczorek Tadeusz, Sajewski Łukasz

Journal of Automation, Electronics and Electrical Engineering

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2022

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Vol. 4, No. 1

7--12

EN

The shuffle algorithm is applied to analysis of the fractional descriptor Roesser type continuous-time linear systems. Using the shuffle algorithm the fractional descriptor linear system is reduced to the equivalent standard system and the system is decomposed into dynamic and static parts. Procedure for computation of the matrices of equivalent standard system and of the dynamical and static parts of the system is proposed.

PL

Algorytm przesuwania jest stosowany do analizy ułamkowych deskryptorowych układów liniowych ciągłych typu Roesser. Stosując algorytm przesuwania, liniowy układ deskryptorowy niecałkowitego rzędu jest redukowany do równoważnego układu standardowego, oraz jest rozkładany na część dynamiczną i statyczną. Zaproponowano procedurę obliczania macierzy równoważnego układu standardowego oraz metodę obliczania części dynamicznej i statycznej.

9

Articulations and Products of Transition Systems and their Applications to Petri Net Synthesis

Devillers Raymond

Fundamenta Informaticae

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2021

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Vol. 183, nr 1-2

1--31

EN

In order to speed up the synthesis of Petri nets from labelled transition systems, a divide and conquer strategy consists in defining decompositions of labelled transition systems, such that each component is synthesisable iff so is the original system. Then corresponding Petri Net composition operators are searched to combine the solutions of the various components into a solution of the original system. The paper presents two such techniques, which may be combined: products and articulations. They may also be used to structure transition systems, and to analyse the performance of synthesis techniques when applied to such structures.

10

Effect of Black Cherry (Prunus serotina) Litter Extracts on Germination and Growth of Scots Pine (Pinus sylvestris) Seedlings

Bączek Paulina, Halarewicz Aleksandra

Polish Journal of Ecology

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2019

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Vol. 67, nr 2

137--147

EN

In the managed forest of temperate Europe, black cherry (Prunus serotina) is one of the most important invader species. Among the ecological traits enabling its expansion in forest stands, the role of chemical compounds released naturally by this plant into the environment still remains unclear. The aim of this study was to determine the influence of black cherry leaf litter on the germination and growth of Scots pine (Pinus sylvestris) seedlings. Laboratory bioassays with extracts from newly fallen and decomposed leaves showed a phytotoxic effect on root elongation and a slightly weaker negative effect on stem growth of pine shoots. The inhibitory effect increased with the gradient of leaf extract concentration. Furthermore, a significant negative correlation was observed between condensed tannin content in decomposed leaf litter of the black cherry and the pine root growth. The results are discussed in the context of black cherry litter properties which could interfere with natural regeneration of pine forests.

11

Technology mapping oriented to adaptive logic modules

Kubica M., Kania D.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 5

947--956

EN

This paper presents an innovative method of technology mapping of the circuits in ALM appearing in FPGA devices by Intel. The essence of the idea is based on using triangle tables that are connected with different configurations of blocks. The innovation of the proposed method focuses on the possibility of choosing an appropriate configuration of an ALM block, which is connected with choosing an appropriate decomposition path. The effectiveness of the proposed technique of technology mapping is proved by experiments conducted on combinational and sequential circuits.

12

Stability analysis of positive linear systems by decomposition of the state matrices into symmetrical and antisymmetrical parts

Kaczorek T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 4

761--768

EN

The stability of positive linear continuous-time and discrete-time systems is analyzed by the use of the decomposition of the state matrices into symmetrical and antisymmetrical parts. It is shown that: 1) The state Metzler matrix of positive continuous-time linear system is Hurwitz if and only if its symmetrical part is Hurwitz; 2) The state matrix of positive linear discrete-time system is Schur if and only if its symmetrical part is Hurwitz. These results are extended to inverse matrices of the state matrices of the positive linear systems.

13

Evaluation of the practicability of the decomposition and equivalent substitution method in the analysis of reliability of the sewage system

Kubala M., Królikowska J., Wawrentowicz D.

Technical Transactions

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2018

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Vol. 115, iss. 5

119--127

EN

The work compares the accuracy of calculations of the reliability parameters of the sewerage network using the Decomposition and Equivalent Replacement (MDE) method, proposed by Yu. A. Yermolin and M.I. Alekseev [3], definitely simpler and less onerous in relation to the graph method. Comparing the results of calculations with both methods, applied to a simple network, one can come to the conclusion that the MDE calculations in simple cases give satisfactory accuracy. However, it would be necessary to check whether, as the complexity increases, this accuracy is still satisfactory.

PL

W pracy porównano dokładność obliczeń parametrów niezawodnościowych sieci kanalizacyjnej metodą dekompozycji i ekwiwalentnej zamiany (MDE), zaproponowaną przez Ju. A. Jermolina i M.I. Alieksjejewa [3], zdecydowanie prostszą i mniej uciążliwą w stosunku do metody grafów. Porównując wyniki obliczeń obiema metodami, zastosowane do prostej sieci, można dojść do wniosku, że obliczenia metodą MDE w prostych przypadkach dają zadowalającą dokładność. Należałoby jednak sprawdzić, czy w miarę wzrostu złożoności, dokładność ta jest nadal zadowalająca.

14

Decomposition of the Kenticha mangano-tantalite ore by HF/H2SO4 and KOH fusion

Berhe G. G., Velázquez del Rosario A., Tadesse B., Yimam A., Woldetinsae G.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

406--414

EN

In this study, the decomposition behavior of Ta and Nb from the mangano-tantalite ore was investigated using HF/H2SO4 mixture and KOH fusion. The effects of reaction time, decomposition temperature, acid and alkaline concentrations, and particle size on the dissolution process were examined. Higher decomposition rates were achieved at 6:2 mol/dm3 ratio of HF and H2SO4, and with the addition of 10 g KOH in the alkali fusion step. In addition, similar trends in decomposition rates between two agents (HF/H2SO4 and KOH) and comparable dissolution performances were observed. The increase in the decomposition temperature initially increased the decomposition rate of mangano-tantalite for the two systems considered in this study. However, no significant change in the leaching rate of Ta and Nb was observed beyond 50 °C for the HF/H2SO4 system and above 400 °C when using the KOH fusion process. The elemental and compositional analyses of the leached residues using XRF, XRD, and FT-IR spectroscopy indicated that the acid (mixture of HF and H2SO4) decomposition resulted in slightly better dissolution performance for Ta compared with the alkaline fusion method. Overall, the results indicated that KOH can be a suitable alternative decomposition agent to the volatile, corrosive and toxic HF in the hydrometallurgical processing of tantalite ores.

15

A concept of reliability assessment simulation model using systems structural decomposition

Młynarski S., Pilch R., Smolnik M., Szybka J., Wiązania G.

Journal of KONBiN

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2018

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No. 46

51--74

EN

The paper presents a concept of reliability estimation of the renewable technical systems consisting of the objects functioning in koon structures. The estimation is performed using computer simulation. Practical dependence between the failure of the entire system and the failures of the objects and elements from which the objects are made are taken into account as the result of the structural decomposition of the system conducted.

PL

W artykule przedstawiono koncepcję szacowania niezawodności odnawialnych układów technicznych składających się z obiektów funkcjonujących w strukturach typu k z n, przy wykorzystaniu symulacji komputerowej. Występujące w praktyce zależności między uszkodzeniem układu a uszkodzeniami obiektów go tworzących i elementów, z których składają się obiekty, uwzględniono poprzez wykonaną dekompozycję strukturalną układu.

16

Synthesis and Study of the Thermal and Ballistic Properties of SMX

Sizov V. A., Pleshakov D. V., Asachenko A. F., Topchiy M. A., Nechaev M. S.

Central European Journal of Energetic Materials

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2018

|

Vol. 15, no. 1

30--46

EN

The high-density tetranitrate ester 1,4-dinitrato-2,3-dinitro-2,3-bis(nitratomethylene)butane (SMX) was synthesized. The methods of obtaining and isolating the intermediates were optimized. The differences between the syntheses of SMX by a four- and five-step scheme were investigated. Combustion of SMX and its catalysis was studied. The possibility of replacing NG as the main plasticizer in a double-base propellant composition was demonstrated. SMX particles were shown to have pronounced crystal faceting using scanning electron microscopy. The decomposition rate equation was determined. The amount of SMX decomposed under isothermal conditions (90 °C) was 0.8 wt.% after 60 min. Thermogravimetric analysis demonstrated that heating SMX results in two different processes – decomposition and evaporation, with SMX evaporating faster than it decomposes.

17

Decomposition of hydrogen perodixe - kinetics and review of chosen catalysts

Pędziwiatr P., Mikołajczyk F., Zawadzki D., Mikołajczyk K., Bedka A.

Acta Innovations

|

2018

|

no. 26

45--52

EN

Hydrogen peroxide is a chemical used in oxidation reactions, treatment of various inorganic and organic pollutants, bleaching processes in pulp, paper and textile industries and for various disinfection applications. It is a monopropellant, which, when purified, is self-decomposing at high temperatures or when a catalyst is present. Decomposing to yield only oxygen and water(disproportionation), hydrogen peroxide is one of the cleanest, most versatile chemicals available. The catalytic decomposition of hydrogen peroxide allows the use of various catalysts that will increase the rate of decomposition. Comparison and description of the most commonly used catalysts were presented in this review.

18

Wpływ warunków środowiska wodnego na rozkład bisfenolu A

Dudziak M.

Proceedings of ECOpole

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2017

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Vol. 11, No. 1

131--139

PL

Bisfenol A to związek chemiczny stosowany do produkcji tworzyw sztucznych. Współcześnie identyfikowany jest on w środowisku wodnym. W pracy podjęto badania dotyczące oceny wpływu warunków środowiska wodnego na rozkład bisfenolu A. Przedmiot badań stanowiły różne roztwory wodne sporządzone na bazie wody zdejonizowanej lub powierzchniowej z dodatkiem wzorca bisfenolu A w stężeniu 1 mg/dm3. Do wybranych roztworów dodawano pożywkę mineralną lub wodę powierzchniową, która to stanowiła źródło zarówno substancji organicznych, jak i nieorganicznych oraz mikroorganizmów. Opcjonalnie wybrane roztwory były przetrzymywane w ciemni lub w świetle słonecznym oraz napowietrzane. Roztwory po biodegradacji poddano również ocenie toksykologicznej z użyciem testu enzymatycznego z bakteriami bioluminescencyjnymi Aliivibrio fischeri, testu przeżywalności ze skorupiakami Daphnia magna oraz testu wzrostowego z rośliną wodną Lemna minor. Określono, że rozkład bisfenolu A w środowisku wodnym jest niewielki i zachodzi głównie pod wpływem światła słonecznego przy udziale mikroorganizmów. Istotna jest również obecność w środowisku wodnym soli mineralnych. Natomiast dokonana ocena toksykologiczna roztworów podczas badań biodegradacyjnych wykazała, że charakteryzują się one różną toksycznością. Klasa toksyczności roztworu zależała także od rodzaju użytego organizmu wskaźnikowego, co świadczy o ich różnej wrażliwości na działanie bisfenolu A. Wysoką toksyczność odnotowano w przypadku bakterii bioluminescencyjnymi Aliivibrio fischeri po 14 dobach trwania badań biodegradacyjnych.

EN

Bisphenol A is a compound used to produce plastics. Today, it is identified in the aquatic environment. As part of the work there are performed studies to determine the effect of the aquatic environment conditions on the decomposition of bisphenol A. As the subject of research there were used different aqueous solutions prepared on the basis of deionized or surface water with addition of a bisphenol A standard at concentration of 1 mg/dm3. To the selected solutions it was added the mineral medium or surface water, which was the source of both organic materials and inorganic compounds and microorganisms. Optionally, the selected solutions had been kept in the dark or in the light of sun, and they had been aerated. Solutions after biodegradation were also subjected of the toxicological evaluation with application of the enzymatic test using bioluminescent bacteria Aliivibrio fischeri, survival test using shellfish Daphnia magna and the growth test of aquatic plant Lemna minor. It was determined that the decomposition of bisphenol A in an aquatic environment is low and it is mainly under the influence of sunlight, with the participation of microorganisms. The presence of mineral salts in aquatic environment is also important. on the other hand, the toxicological assessment of solutions, which was made during testing biodegradation, showed that they have a different toxicity. Toxicity class of the solution also depended on the type of applied indicator, which proves their differences in sensitivity to bisphenol A. High toxicity was noted in the case of bioluminescent bacteria Aliivibrio fischeri after 14 days of the biodegradation study.

19

Decomposition Analysis of the Greenhouse Gas Emissions in the European Union

Drastichová M.

Problemy Ekorozwoju

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2017

|

Vol. 12, nr 2

27--35

EN

Climate change is a significant threat to sustainable development (SD). Using the Log-Mean Divisia Index Method (LMDI) a decomposition of the data on the greenhouse gas (GHG) emissions in the European Union (EU) in 2000 -2013 is carried out. To detect if decoupling of the environmental variable represented by the GHG emissions from the economic variable represented by the GDP was taking place in the EU economy, the changes of the GHG emissions were divided into three effects. These factors include the economic activity (scale), the composition or structure of the EU economy with respect to the countries, and GHG intensity of the countries. The aim of the paper is to detect if decoupling of the GHG emissions from the GDP development in the EU took place and to detect the factors of this development. The intensity effect was mainly responsible for the reduction of the GHG emissions in the EU while the scale effect contributed to their increase. The role of the composition effect was only marginal; however, it was positive. As the intensity effect often showed the high negative values, the total effect was often negative as well, which means that decoupling of GHG emissions from GDP took place.

PL

Zmiany klimatyczne stanowią istotne zagrożenie dla zrównoważonego rozwoju (ZR). Przy pomocy metody LMDI przeprowadzono analizę rozkładu emisji gazów cieplarnianych w krajach Unii Europejskiej (UE) w okresie lat 2010-2013. Aby sprawdzić, czy decoupling zmiennej środowiskowej reprezentowanej przez emisję gazów cieplarnianych od zmiennej ekonomicznej reprezentowanej przez PKB w kontekście zmian emisji gazów cieplarnianych zachodzi we Wspólnocie, uwzględniono następujące efekty: aktywność ekonomiczną (skalę), skład i strukturę europejskiej ekonomii z uwzględnieniem różnic charakterystycznych dla poszczególnych krajów i poziomu ich emisji gazów cieplarnianych. Celem artykułu jest potwierdzenie, czy decoupling emisji gazów cieplarnianych od wzrostu PKB faktycznie zachodzi i jakie czynniki na niego wpływają. Efekt intensywności okazał się być odpowiedzialny głównie za zmniejszenie emisji gazów cieplarnianych w Europie, podczas gdy efekt skali przyczyniał się do wzrostu tej emisji. Efekt struktury odgrywał rolę marginalną, choć pozytywną. Efekt intensywności zwykle charakteryzował się wysokimi wartościami ujemnymi, to samo odnosiło się do efektu całkowitego, co oznacza, że decoupling emisji gazów cieplarnianych od PKB faktycznie zachodzi.

20

Szacowanie wielkości zrzutu nieoczyszczonych ścieków w wyniku uszkodzenia sieci kanalizacyjnej grawitacyjnej z wykorzystaniem metod analizy niezawodnościowej

Królikowska J., Królikowski A., Wawrentowicz D.

Gaz, Woda i Technika Sanitarna

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2017

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Nr 7

308--312

PL

W artykule przedstawiono główne cechy systemów kanalizacyjnych, jako obiektów złożonych (o strukturze typu "drzewo") i pracujących w zmiennych, trudnych często do przewidzenia, warunkach. Do oceny wielkości zrzutu nieoczyszczonych ścieków w wyniku uszkodzenia sieci przeanalizowano zastosowanie metody równań stanów oraz metody dekompozycji i ekwiwalentowania.

EN

The article points out main features of the sewage systems, which are complex objects (possessing "tree" structure) working in changing, often hard to predict, environment. In order to estimate the quantity of untreated sewers' drop, which resulted from failures of the sewage system, author has analysed the usage of state-space model as well as decomposition and equivalent model.