Filters
total: 1371
-
Catalog
displaying 1000 best results Help
Search results for: GRAPH COLORING
-
Magnetoacoustic Heating in Nonisentropic Plasma Caused by Different Kinds of Heating-Cooling Function
PublicationThe nonlinear phenomena which associate with magnetoacoustic waves in a plasma are analytically studied. A plasma is an open system with external inflow of energy and radiation losses. A plasma’s flow may be isentropically stable or unstable. The nonlinear phenomena occur differently in dependence on stability or instability of a plasma’s flow. The nonlinear instantaneous equation which describes dynamics of nonwave entropy mode...
-
Influence of cooling rate and additives on low-temperature properties of asphalt mixtures in the TSRST
PublicationThe paper presents the results and analysis of low-temperature properties of asphalt mixtures according to Thermal Stress Restrained Specimen Test (TSRST) and Indirect Tensile Test methods. Different groups of bitumen were investigated: neat, SBS-modified and highly SBS-modified. Influence of cooling rates (1 C/h, 3 C/h, 5 C/h and 10 C/h) and additives (aramid fibres and crumb rubber) was identified as well. Moreover, for each...
-
Slowly-closing valve behaviour during steam machine accelerated start-up
PublicationThe paper discusses the state of stress in a slowly-closing valve during accelerated start-up of a steam turbine. The valve is one of the first components affected by high temperature gradients and is a key element on which the power, efficiency and safety of the steam system depend. The authors calibrated the valve model based on experimental data and then performed extended Thermal-FSI analyses relative to experiment. The issue...
-
Closing the gap – the opportunity for sustainability and smart transition in the Central and East Europe countries
PublicationFor almost half a century the countries of CEE were part of- or were remaining under the influence of- the Soviet Union what caused gaping difference in the starting line towards sustainability. Here the prefabricated concrete blocks of flats were being built at the scale unseen in the western countries. Those buildings, approximately a quarter of the residential market, are in a structurally sound condition to last another five...
-
Switched-capacitor DC-DC converters in arbitrary switching mode - topologically derived resistive models based on incremental graph approach.
PublicationIn the preceding paper we reviewed some of modeling approaches aimed at systematic formulation and solution of switched capacitor DC-DC converters. In our review, special attention was paid to computationally efficient and mathematically elegant methods. In so doing we had tried to demonstrate the virtues of unified Incremental Graph (IG) approach. Incremental Graph is, in concept, a tool originally created for analysis and synthesis...
-
Reconfiguring Minimum Dominating Sets in Trees
PublicationWe provide tight bounds on the diameter of γ-graphs, which are reconfiguration graphs of the minimum dominating sets of a graph G. In particular, we prove that for any tree T of order n ≥ 3, the diameter of its γ-graph is at most n/2 in the single vertex replacement adjacency model, whereas in the slide adjacency model, it is at most 2(n − 1)/3. Our proof is constructive, leading to a simple linear-time algorithm for determining...
-
Derandomizing random walks in undirected graphs using locally fair exploration strategies
PublicationW pracy rozważono problem eksploracji anonimowego nieskierowanego grafu przez bezpamięciowego robota. Zaprojektowane strategie eksploracji cechują się własnością lokalnej sprawiedliwości, tj. kolejne krawędzie trawersowane przez robota wybierane są na podstawie lokalnych informacji tak, aby zapewnić równomierne wykorzystanie krawędzi w sensie pewnego kryterium. Okazuje się, że odpowiedni dobór kryterium jest kluczowy do zapewnienia...
-
Minimum vertex ranking spanning tree problem for chordal and proper interval graphs
PublicationW pracy rozważamy problem szukania, dla danego grafu prostego, drzewa spinającego, którego uporządkowana liczba chromatyczna jest minimalna. K.~Miyata i inni dowiedli w [Np-hardness proof and an approximation algorithm for the minimum vertex ranking spanning tree problem,Discrete Appl. Math. 154 (2006) 2402-2410], że odpowiedni problem decyzyjny jest NP-trudny już w przypadku pytania o istnienie uporządkowanego 4-pokolorowania....
-
Wheat Bread with Grape Seeds Micropowder: Impact on Dough Rheology and Bread Properties
Publication -
Zastosowanie komputerów w dziedzinie wyszukiwania strategii optymalnych w grach logicznych
PublicationProblem jaki stanowi wyszukiwanie strategii optymalnej w grach logicznych jest bardzo złożony. Można go podzielić na następujące podproblemy: obliczeniowy, pamięciowy oraz operacji wejścia/wyjścia. Jednak rosnąca z roku na rok siła obliczeniowa komputerów, ilość pamięci oraz prędkość transferu danych pomiędzy podzespołami zarówno lokalnymi jak i rozproszonymi, a także wzrost skuteczności wykorzystywanych technik algorytmicznych...
-
Musical Metadata Retrieval with Flow Graphs, in Rough Sets and Current Trends in Computing.
PublicationW pracy opisano metody wyszukiwania muzyki w Internecie w oparciu o opis semantyczny. W eksperymentach wykorzystano opis muzyczny stosowany w bazie CDDB. Zaprezentowano metodę grafów przepływowych zaproponowaną przez Pawlaka.
-
How to meet when you forget: log-space rendezvous in arbitrary graphs
PublicationProblem rendezvous został dogłębnie zbadany, zarówno dla agendów anonimowych jak i poetykietowanych. zbadano też problem eksploracji grafu za pomocą agentów mobilnych.
-
Multimodal Network Based Graphs of Primitives Storage Concept for Web Mining CBIR
Publication -
Scheduling of unit-length jobs with bipartite incompatibility graphs on four uniform machines
PublicationThe problem of scheduling n identical jobs on 4 uniform machines with speeds s1>=s2>=s3>=s4 is considered.The aim is to find a schedule with minimum possible length. We assume that jobs are subject to mutual exclusion constraints modeled by a bipartite incompatibility graph of degree delta. We show that the general problem is NP-hard even if s1=s2=s3. If, however, delta<5 and s1>12s2 s2=s3=s4, then the problem can be solved to...
-
How to meet when you forget: log-space rendezvous in arbitrary graphs
PublicationTwo identical (anonymous) mobile agents start from arbitrary nodes in an a priori unknown graph and move synchronously from node to node with the goal of meeting. This rendezvous problem has been thoroughly studied, both for anonymous and for labeled agents, along with another basic task, that of exploring graphs by mobile agents. The rendezvous problem is known to be not easier than graph exploration. A well-known recent result...
-
Scheduling of identical jobs with bipartite incompatibility graphs on uniform machines. Computational experiments
PublicationWe consider the problem of scheduling unit-length jobs on three or four uniform parallel machines to minimize the schedule length or total completion time. We assume that the jobs are subject to some types of mutual exclusion constraints, modeled by a bipartite graph of a bounded degree. The edges of the graph correspond to the pairs of jobs that cannot be processed on the same machine. Although the problem is generally NP-hard,...
-
Scheduling of unit-length jobs with cubic incompatibility graphs on three uniform machines
PublicationWe consider the problem of scheduling n identical jobs on 3 uniform machines with speeds s1, s2, and s3 to minimize the schedule length. We assume that jobs are subject to some kind of mutual exclusion constraints, modeled by a cubic incompatibility graph. We how that if the graph is 2-chromatic then the problem can be solved in O(n^2) time. If the graph is 3-chromatic, the problem becomes NP-hard even if s1>s2=s3.
-
Exploiting multi-interface networks: Connectivity and Cheapest Paths
PublicationLet G = (V,E) be a graph which models a set of wireless devices (nodes V) that can communicate by means of multiple radio interfaces, according to proximity and common interfaces (edges E). The problem of switching on (activating) the minimum cost set of interfaces at the nodes in order to guarantee the coverage of G was recently studied. A connection is covered (activated) when the endpoints of the corresponding edge share at...
-
Application of a smartphone based spectrophotometer for rapid in-field determination of nitrite and chlorine in environmental water samples
Publication -
Recurrence times in the Morse sets for a two-dimensional discrete neuron model (low resolution)
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper “Topological-numerical analysis of a two-dimensional discrete neuron model” by Paweł Pilarczyk, Justyna Signerska-Rynkowska and Grzegorz Graff. A preprint of this paper is available at https://doi.org/10.48550/arXiv.2209.03443.
-
COMPARISON OF HEAT TRANSFER CHARACTERISTICS IN SURFACE COOLING WITH BOILING MICROJETS OF WATER, ETHANOL AND HFE7100
PublicationThe basis of microjet technology is to produce laminar jets which when impinging the surface have a very high kinetic energy at the stagnation point. Boundary layer is not formed in those conditions, while the area of film cooling has a very high turbulence resulting from a very high heat transfer coefficient. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm...
-
Evaluation of turning with different cooling-lubricating techniques in terms of surface integrity and tribologic properties
Publication -
Numerical investigations of the engine cooling system in a small power vesel pod propulsion system
PublicationThe development of electronics and electrotechnology enabled to put electric motors of the alternating current in the pod and to use them for the main drive of ships. A lot of heat which must be picked up from the system is a problem which is turning up at applying the system of this type. Many big ships lately contended with these problems. Building the small propeller for the boat powered with solar power we decided to check...
-
Experimental investigation on heat pipes supported by soy wax and lauric acid for electronics cooling
PublicationThis paper presents an experimental study of heat pipes for electronics cooling that were supported by energy storage materials (i.e. phase change materials - PCMs) coated at the adiabatic section. The PCMs utilized included two materials, namely lauric acid and soy wax, the latter being considered as a more cost-effective alternative. The study focused on three different powers: 20 W, 25 W, and 30 W. Both heating, cooling, and...
-
Water Demineralization by Membrane Distillation Utilizing Cooling Water From Municipal Waste Incinerator
Publication -
Effect on Phytochemical Content and Microbial Contamination of Actinidia Fruit after Shock Cooling and Storage
Publication -
Comparison of heat transfer characteristics in surface cooling with boiling microjets of water, ethanol and HFE7100
PublicationThe basis of microjet technology is to produce jets which impinge the surface at the stagnation point with a very high kinetic energy. Main objective of this paper was to investigate the physical phenomena occurring on solid surfaces upon impingement of the single microjet in case of three fluids, namely water, ethanol and HFE7100. Intense heat transfer in the impact zone of microjet has been examined and described with precise...
-
RecA Proteins from Deinococcus geothermalis and Deinococcus murrayi - Cloning, Purification and Biochemical Characterisation
PublicationEscherichia coli RecA plays a crucial role in recombinational processes, the induction of SOS response and mutagenic lesion bypasses. It has also been demonstrated that RecA protein is indispensable when it comes to the reassembly of shattered chromosomes in gamma-irradiated Deinococcus radiodurans, one of the most radiation-resistant organisms known. Moreover, some functional differences between E. coli and D. radiodurans RecA...
-
Interaction of Acoustic and Thermal Modes in the Gas with Nonequilibrium Chemical Reactions: Possibilities of Acoustic Cooling
PublicationNonlinear generation of thermal mode during propagation of dominative sound in a chemically reacting gas is considered. The dynamic equation of excess temperature associated with the thermal mode is derived. It is instantaneous and includes quadratic nonlinear acoustic source reflecting the nonlinear character of interaction between acoustic and non-acoustic types of gas motion. Both periodic and aperiodic sound may be considered...
-
Influence of steam cooking on pro-health properties of Small and Large variety of Momordica charantia
PublicationSteam cooking is one of the most common preparations of Momordicacharantia dishes. This method improved the tastiness of the fruits but at the same time, some changes occurred in the volatile and non-volatile parts of their food matrices. In this study, for the first time these properties were correlated with the found substances affecting the bioactivity of this fruit. Two varieties of Momordicacharantia were analysed and compared....
-
Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublicationJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
-
A study of jet impingement cooling enhancement by concave and convex heat sink shape modifications
PublicationThe rising demand for efficient cooling technologies is a strong driver of extensive research in this area. This trend is particularly strong in turbines and microprocessors technology. Presented study is focused on the jet impingement cooling concept, which is used in various configurations for many years. The potential of the heat sink shape modification is not yet fully explored. Available literature suggests that average Nusselt...
-
Bond-graphs based modelling of hybrid energy systems with permanent magnet brushless machines
PublicationW referacie przedstawiono metodę grafów wiązań (GW) w zastosowaniu do modelowania hybrydowych systemów energetycznych z bezszczotkowymi maszynami elektrycznymi o magnesach trwałych. W części pierwszej referatu omówiono ogólne formalizm GW. Następnie przedstawiono kolejno: ogólną strukturę modelu hybrydowego systemu energetycznego w ujęciu GW; założenia modelowania maszyn elektrycznych w ujęciu GW, model silnika bezszczotkowego...
-
The complexity of the L(p,q)-labeling problem for bipartite planar graphs of small degree
PublicationW pracy pokazano, że problem L(p,q)-kolorowania przy użyciu ''t'' kolorów jest NP-zupełny nawet w wersji ograniczonej do grafów planarnych dwudzielnych małego stopnia, nawet dla stosunkowo niewielkich wartości ''t''. Jako wniosek z uzyskanych wyników stwierdzono, że problem L(2,1)-kolorowania grafów planarnych przy użyciu 4 kolorów jest NP-zupełny, a także że problem L(p,q)-kolorowania grafów o maksymalnym stopniu 4 jest NP-zupełny...
-
Bond-graphs based modelling of hybrid energy systems with permanent magnet brushless machines
PublicationW referacie przedstawiono metodę grafów wiązań (GW) w zastosowaniu do modelowania hybrydowych systemów energetycznych z bezszczotkowymi maszynami elektrycznymi o magnesach trwałych. W części pierwszej referatu omówiono ogólne formalizm GW. Następnie przedstawiono kolejno: ogólną strukturę modelu hybrydowego systemu energetycznego w ujęciu GW; założenia modelowania maszyn elektrycznych w ujęciu GW, model silnika bezszczotkowego...
-
Characterizing the Performance of <span class="sc">xor</span> Games and the Shannon Capacity of Graphs
PublicationIn this Letter we give a set of necessary and sufficient conditions such that quantum players of a two-party xor game cannot perform any better than classical players. With any such game, we associate a graph and examine its zero-error communication capacity. This allows us to specify a broad new class of graphs for which the Shannon capacity can be calculated. The conditions also enable the parametrization of new families of games...
-
Bond-graphs based modelling of hybrid energy systems with permanent magnet brushless machines
PublicationW referacie przedstawiono metodę grafów wiązań (GW) w zastosowaniu do modelowania hybrydowych systemów energetycznych z bezszczotkowymi maszynami o magnesach trwałych (BMMT). W części pierwszej referatu omówiono ogólne formalizm GW. Następnie przedstawiono kolejno: ogólną strukturę modelu hybrydowego systemu energetycznego w ujęciu GW; założenia modelowania maszyn elektrycznych w ujęciu GW, model SBMT w ujęciu GW dla potrzeb modelowania...
-
Conley-Morse graphs for a two-dimensional discrete neuron model (low resolution)
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper “Topological-numerical analysis of a two-dimensional discrete neuron model” by Paweł Pilarczyk, Justyna Signerska-Rynkowska and Grzegorz Graff. A preprint of this paper is available at https://doi.org/10.48550/arXiv.2209.03443.
-
Conley-Morse graphs for a two-dimensional discrete neuron model (limited range)
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper “Topological-numerical analysis of a two-dimensional discrete neuron model” by Paweł Pilarczyk, Justyna Signerska-Rynkowska and Grzegorz Graff. A preprint of this paper is available at https://doi.org/10.48550/arXiv.2209.03443.
-
Conley-Morse graphs for a two-dimensional discrete neuron model (full range)
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper “Topological-numerical analysis of a two-dimensional discrete neuron model” by Paweł Pilarczyk, Justyna Signerska-Rynkowska and Grzegorz Graff. A preprint of this paper is available at https://doi.org/10.48550/arXiv.2209.03443.
-
Experimental and theoretical studies on the photodegradation of 2-ethylhexyl 4-methoxycinnamate in the presence of reactive oxygen and chlorine species
Publication2-Ethylhexyl 4-methoxycinnamate (EHMC) is one of the most commonly used sunscreen ingredient. In this study we investigated photodegradation of EHMC in the presence of such common oxidizing and chlorinating systems as H2O2, H2O2/HCl, H2O2/UV, and H2O2/HCl/UV. Reaction products were detected by gas chromatography with a mass spectrometric detector (GC-MS). As a result of experimental studies chloro-substituted 4-methoxycinnamic...
-
Extraction pathways and purification strategies towards carminic acid as natural-based food colorant: A comprehensive review
PublicationAs a current trend of fabricating healthier products, food manufacturing companies seek for natural-based food colorant aiming to replace the synthetic ones, which apart from meeting sensorial and organoleptic aspects, they can also act as health promoters offering additional added value. Carminic acid is a natural based food colorant typically found in several insect taxa. However, there are current approaches which pursue the...
-
An optimised placement of the hard quality sensors for a robust monitoring of the chlorine concentration in drinking water distribution systems
PublicationThe problem of an optimised placement of the hard quality sensors in drinking water distribution systemsunder several water demand scenarios for a robust monitoring of the chlorine concentration is formulatedin this paper. The optimality is understood as achieving a desired trade off between the sensors and theirmaintenance costs and the accuracy of estimation of the chlorine concentration. The contribution of thiswork is a comprehensive...
-
Wojciech Wojnowski dr inż.
PeopleUkończył V Liceum Ogólnokształcące w Gdańsku w klasie o profilu matematyczno-fizycznym z wykładowym językiem angielskim. W 2009 roku rozpoczął studia na Wydziale Chemicznym PG na kierunku technologia chemiczna, uzyskując w 2012 roku tytuł inżyniera, a w 2013 tytuł magistra. W latach 2013–2015 studiował sinologię na Uniwersytecie w Nankinie dzięki uzyskaniu Stypendium Rządu ChRL. Po powrocie do Polski w 2015 roku rozpoczął studia...
-
Conley-Morse graphs for a non-linear Leslie population model with 2 varying parameters
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper "A database schema for the analysis of global dynamics of multiparameter systems" by Z. Arai, W. Kalies, H. Kokubu, K. Mischaikow, H. Oka, P. Pilarczyk, published in SIAM Journal on Applied Dynamical Systems (SIADS),...
-
Conley-Morse graphs for a non-linear Leslie population model with 3 varying parameters
Open Research DataThis dataset contains selected results of rigorous numerical computations conducted in the framework of the research described in the paper "A database schema for the analysis of global dynamics of multiparameter systems" by Z. Arai, W. Kalies, H. Kokubu, K. Mischaikow, H. Oka, P. Pilarczyk, published in SIAM Journal on Applied Dynamical Systems (SIADS),...
-
Heat transfer to car engine cooling system - influence of coolant flow through engine block
PublicationW artykule przedstawiono wyniki badań doświadczalnych nad wpływem nastawianej wydajności pompy cieczy na strumień odbieranego ciepła w silniku spalinowym. Wykorzystano hamownię silnikową z silnikiem o zapłonie iskrowym o objętości skokowej 1.8 dm^3. Przyjęto obciążenia silnika oporami ruchu samochodu na biegu bezpośrednim.
-
Structural and Microhardness Changes After Turning of the AISI 1045 Steel for Minimum Quantity Cooling Lubrication
Publication -
Improvement of machinability of Ti and its alloys using cooling-lubrication techniques: a review and future prospect
Publication -
The features of steel surface hardening with high energy heating by high frequency currents and shower cooling
Publication