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Parallel Shared-Memory Isogeometric Residual Minimization (iGRM) for Three-Dimensional Advection-Diffusion Problems [chapter]

Marcin Łoś, Judit Munoz-Matute, Krzysztof Podsiadło, Maciej Paszyński, Keshav Pingali
2020 Lecture Notes in Computer Science  
In this paper, we present a residual minimization method for three-dimensional isogeometric analysis simulations of advectiondiffusion equations. First, we apply the implicit time integration scheme for the three-dimensional advection-diffusion equation. Namely, we utilize the Douglas-Gunn time integration scheme. Second, in every time step, we apply the residual minimization method for stabilization of the numerical solution. Third, we use isogeometric analysis with B-spline basis functions
more » ... the numerical discretization. We perform alternating directions splitting of the resulting system of linear equations, so the computational cost of the sequential LU factorization is linear O(N ). We test our method on the three-dimensional simulation of the advectiondiffusion problem. We parallelize the solver for shared-memory machine using the GALOIS framework.
doi:10.1007/978-3-030-50436-6_10 fatcat:b5fynyyvira77gt4ennvxdtayq

Microstructure and Properties of TiB2 Composites Produced by Spark Plasma Sintering with the Addition of Ti5Si3

Agnieszka Twardowska, Marcin Podsiadło, Iwona Sulima, Krzysztof Bryła, Paweł Hyjek
2021 Materials  
Titanium diboride (TiB2) is a hard, refractory material, attractive for a number of applications, including wear-resistant machine parts and tools, but it is difficult to densify. The spark plasma sintering (SPS) method allows producing TiB2-based composites of high density with different sintering aids, among them titanium silicides. In this paper, Ti5Si3 is used as a sintering aid for the sintering of TiB2/10 wt % Ti5Si3 and TiB2/20 wt % Ti5Si3 composites at 1600 °C and 1700 °C for 10 min.
more » ... phase composition of the initial powders and produced composites was analyzed by the X-ray diffraction method using CuKα radiation. The microstructure was examined using scanning electron microscopy, accompanied by energy-dispersive spectroscopy (EDS). The hardness was determined using a diamond indenter of Vickers geometry loaded at 9.81 N. Friction–wear properties were tested in the dry sliding test in a ball-on-disc configuration, using WC as a counterpart material. The major phases present in the TiB2/Ti5Si3 composites were TiB2 and Ti5Si3. Traces of TiC were also identified. The hardness of the TiB2/Ti5Si3 composites was in the range of 1860–2056 HV1 and decreased with Ti5Si3 content, as well as the specific wear rate Wv. The coefficient of friction for the composites was in the range of 0.5–0.54, almost the same as for TiB2 sinters. The main mechanism of wear was abrasive.
doi:10.3390/ma14143812 fatcat:6l67s4tvv5hdhioiisni74k4b4

An Algorithm for Tensor Product Approximation of Three-Dimensional Material Data for Implicit Dynamics Simulations [chapter]

Krzysztof Podsiadło, Marcin Łoś, Leszek Siwik, Maciej Woźniak
2018 Lecture Notes in Computer Science  
In the paper, a heuristic algorithm for tensor product approximation with B-spline basis functions of three-dimensional material data is presented. The algorithm has an application as a preconditioner for implicit dynamics simulations of a non-linear flow in heterogeneous media using alternating directions method. As the simulation use-case, a non-stationary problem of liquid fossil fuels exploration with hydraulic fracturing is considered. Presented algorithm allows to approximate the
more » ... ity coefficient function as a tensor product what in turn allows for implicit simulations of the Laplacian term in the partial differential equation. In the consequence the number of time steps of the nonstationary problem can be reduced, while the numerical accuracy is preserved.
doi:10.1007/978-3-319-93701-4_12 fatcat:635u775bjndulh3c44eh264dbm

A Massively Parallel Algorithm for the Three-Dimensional Navier-Stokes-Boussinesq Simulations of the Atmospheric Phenomena [chapter]

Maciej Paszyński, Leszek Siwik, Krzysztof Podsiadło, Peter Minev
2020 Lecture Notes in Computer Science  
We present a massively parallel solver using the direction splitting technique and stabilized time-integration schemes for the solution of the three-dimensional non-stationary Navier-Stokes-Boussinesq equations. The model can be used for modeling atmospheric phenomena. The time integration scheme utilized enables for efficient direction splitting algorithm with finite difference solver. We show how to incorporate the terrain geometry into the simulation and how to perform the domain
more » ... n. The computational cost is linear O(N ) over each sub-domain, and near to O(N/c) in parallel over 1024 processors, where N is the number of unknowns and c is the number of cores. This is even if we run the parallel simulator over complex terrain geometry. We analyze the parallel scalability experimentally up to 1024 processors over a PROMETHEUS Linux cluster with multi-core processors. The weak scalability of the code shows that increasing the number of subdomains and processors from 4 to 1024, where each processor processes the subdomain of 49 × 49 × 99 internal points (50 × 50 × 100 box), results in the increase of the total computational time from 120 s to 178 s for a single time step. Thus, we can perform a single time step with over 1,128,000,000 unknowns within 3 min. The number of unknowns results from the fact that we have three components of the velocity vector field, one component of the pressure, and one component of the temperature scalar field over 256,000,000 mesh points. The computation of the one time step takes 3 min on a Linux cluster. The direction splitting solver is not an iterative solver; it solves the system accurately since it is equivalent to Gaussian elimination. Our code is interfaced with the mesh generator reading the NASA database and providing the Earth terrain map. The goal of the project is to provide a reliable tool for parallel, fully three-dimensional computations of the atmospheric phenomena.
doi:10.1007/978-3-030-50371-0_8 fatcat:oa5wsntsbvbwdbjgx6ybg3zqwm

Difficulties in funding of VA-ECMO therapy for patients with severe accidental hypothermia

Sylweriusz Kosiński, Tomasz Darocha, Anna Jarosz, Aleksandra Czerw, Paweł Podsiadło, Tomasz Sanak, Robert Gałązkowski, Jacek Piątek, Janusz Konstanty-Kalandyk, Mirosław Ziętkiewicz, Krzysztof Kusza, Łukasz J. Krzych (+1 others)
2017 Anaesthesiology Intensive Therapy  
Severe accidental hypothermia is defined as a core temperature below 28 Celsius degrees. Within the last years, the issue of accidental hypothermia and accompanying cardiac arrest has been broadly discussed and European Resuscitation Council (ERC) Guidelines underline the importance of Extracorporeal Rewarming (ECR) in treatment of severely hypothermic victims. The study aimed to evaluate the actual costs of ECR with VA-ECMO and of further management in the Intensive Care Unit of patients
more » ... ed to the Severe Accidental Hypothermia Centre in Cracow, Poland. Methods: We carried out the economic analysis of 31 hypothermic adults in stage III-IV (Swiss Staging) treated with VA ECMO. Twenty-nine individuals were further managed in the Intensive Care Unit. The actual treatment costs were evaluated based on current medication, equipment, and dressing pricing. The costs incurred by the John Paul II Hospital were then collated with the National Health Service (NHS) funding, assessed based on current financial contract. Results: In most of the cases, the actual treatment cost was greater than the funding received by around 10000 PLN per patient. The positive financial balance was achieved in only 4 (14%) individuals; other 25 cases (86%) showed a financial loss. Conclusion: Performed analysis clearly shows that hospitals undertaking ECR may experience financial loss due to implementation of effective treatment recommended by international guidelines. Thanks to new NHS funding policy since January 2017 such loss can be avoided, what shall encourage hospitals to perform this expensive, yet effective method of treatment.
doi:10.5603/ait.2017.0029 pmid:28643322 fatcat:axqowt3o55h7tdrm5g7lg6skgq

Repetition and reproduction of preclinical medical studies: taking a leaf from the plant sciences with consideration of generalised systematic errors [article]

Jeremy S. C. Clark, Anna Salacka, Agnieszka Boron, Thierry van de Wetering, Konrad Podsiadlo, Kamila Rydzewska, Krzysztof Safranow, Kazimierz Ciechanowski, Leszek Domanski, Andrzej Ciechanowicz
2022 arXiv   pre-print
Reproduction of pre-clinical results has a high failure rate. The fundamental methodology including replication ("protocol") for hypothesis testing/validation to a state allowing inference, varies within medical and plant sciences with little justification. Here, five protocols are distinguished which deal differently with systematic/random errors and vary considerably in result veracity. Aim: to compare prevalence of protocols (defined in text). Medical/plant science articles from 2017/2019
more » ... e surveyed: 713 random articles assessed for eligibility for counts: first (with p-values): 1) non-replicated; 2) global; 3) triple-result protocols; second: 4) replication-error protocol; 5) meta-analyses. Inclusion criteria: human/plant/fungal studies with categorical groups. Exclusion criteria: phased clinical trials, pilot studies, cases, reviews, technology, rare subjects, -omic studies. Abbreviated PICOS question: which protocol was evident for a main result with categorically distinct group difference(s) ? Electronic sources: Journal Citation Reports 2017/2019, Google. Triplication prevalence differed dramatically between sciences (both years p<10-16; cluster-adjusted chi-squared tests): From 320 studies (80/science/year): in 2017, 53 (66%, 95% confidence interval (C.I.) 56%:77%) and in 2019, 48 (60%, C.I. 49%:71%) plant studies had triple-result or triplicated global protocols, compared with, in both years, 4 (5%, C.I. 0.19%:9.8%) medical studies. Plant sciences had a higher prevalence of protocols more likely to counter generalised systematic errors (the most likely cause of false positives) and random error than non-replicated protocols, without suffering from serious flaws found with random-Institutes protocols. It is suggested that a triple-result (organised-reproduction) protocol, with Institute consortia, is likely to solve most problems connected with the replicability crisis.
arXiv:2201.10960v1 fatcat:j3oos33j45eqzafxduaguml2hu

Parallel graph-grammar-based algorithm for the longest-edge refinement of triangular meshes and the pollution simulations in Lesser Poland area

Krzysztof Podsiadło, Albert Oliver Serra, Anna Paszyńska, Rafael Montenegro, Ian Henriksen, Maciej Paszyński, Keshav Pingali
2021 Engineering with Computers  
The code can be downloaded from https://github.com/Podsiadlo/TerrainMesh Generator/ lonestar/graphgrammar2. Here, we present the scalability results for the concurrent code for 24 iterations.  ... 
doi:10.1007/s00366-020-01253-y fatcat:3rvjppvmsvhzvnkxx2bskxbnhq

Environmental Factors Effects on Winter Wheat Competition with Herbicide-Resistant or Susceptible Silky Bentgrass (Apera spica-venti L.) in Poland

Agnieszka Synowiec, Beata Jop, Krzysztof Domaradzki, Cezary Podsiadło, Dorota Gawęda, Roman Wacławowicz, Anna Wenda-Piesik, Mateusz M. Nowakowski, Jan Bocianowski, Katarzyna Marcinkowska, Tadeusz Praczyk
2021 Agronomy  
Environmental factors, including weather and soil conditions, can affect the competitive effects of weeds on crops. This work aimed at a comparison of the competitive abilities of winter wheat toward bentgrass (Apera spica-venti (L.) P. Beauv) with single herbicide resistance, multiple herbicide resistance, or a susceptible biotype in different environmental conditions of Poland. A replacement series competition model was applied in field conditions in 2017–2018 and 2018–2019 across the
more » ... A competitive ratio (CR) was calculated for the relative biomass of plants and grain number. A canonical variate analysis (CVA) was performed for biological parameters and a day-difference in emergence between winter wheat and bentgrass with the hydrothermal coefficient and soil texture in all of the sites in each season separately. Winter wheat emergence was correlated with the amount of precipitation after seeding, and was fastest for five days in humid conditions, and slowest up to 22 days, when the precipitation in October was low. The CVA proved that winter wheat's competitive effects toward the susceptible or herbicide-resistant biotypes of bentgrass are site-specific. During the dry season, the bentgrass biotype with multiple herbicide resistance was more competitive toward winter wheat than the susceptible one. The wheat CR < 1 with regard to biomass and both biomass and the grain number was in 64% and 50% of all the combinations with the resistant biotype. In conclusion, weather affects the competitive effects of winter wheat toward herbicide-susceptible or resistant bentgrass.
doi:10.3390/agronomy11050871 fatcat:ucuxiskiobby3f6m6xwebc2hca

A case of extensive inflammatory changes (osteomyelitis) in an infant's skeleton from the medieval burial ground (11th-12th c) in Wawrzeńczyce (near Krakow)

Małgorzata Kołodziej, Elżbieta Haduch, Arkadiusz Wrębiak, Anita Szczepanek, Beata Podsiadło-Kleinrok, Anna Mazur, Krzysztof Mazur
2015 Collegium Antropologicum  
The aim of this study was to diagnose and describe extensive inflammatory changes in a child's skeleton from Wawrzeńczyce, (the medieval period). The aim of the analysis was to determine the nature of the inflammatory changes and their etiology by means of macroscopic techniques as well as X-ray analysis. The tests revealed that the individual suffered from a hematogenous multifocal osteitis. This condition might have been a result of an acute or sub-acute osteitis, and the untreated form of
more » ... eomyelitis might have contributed to the infection of the entire developing organism, leading to death.
pmid:26040086 fatcat:pj4zbppfvzbklnuzef6wobtb6e

Table des matières

Teresa Rutkowska
2021 Kwartalnik Filmowy  
L'entretien avec Krzysztof Ostrowski 179 Przemysław Kaniecki La vie sur l'écran.  ...  Polański et quelques problèmes de la réception du film 50 Łucja Demby Entre les temps anciens et les temps nouveaux - les traces néo(animistes) et néo(païennes) dans le cinéma polonais 65 Magdalena Podsiadło-Kwiecień  ... 
doi:10.36744/kf.870 fatcat:czq7tbebqjarvh3rjjucikb2vy

Sprawozdanie z konferencji "Od grzechotki do klocków Lego – dawne i współczesne zabawki dziecięce" 7–8 grudnia 2009 Kielce

Kinga Jackowska, Katarzyna Kabacińska
2019 Biuletyn Historii Wychowania  
Dorota Żołądź-Strzelczyk, dr Jolanta Podsiadło, prezydent miasta Kielc Wojciech Lubawski oraz prof. dr hab.  ...  Dorota Żołądź-Strzelczyk, główna pomysłodawczyni i inicjatorka tego spotkania naukowego oraz dr Jolanta Podsiadło.  ... 
doi:10.14746/bhw.2009.25.27 fatcat:udji3ynejvdrpisvky6u5gugaq

Osobnienie

Krzysztof Siwczyk
2019 Poznańskie Studia Polonistyczne. Seria Literacka  
Jacek Podsiadło natomiast wiódł żywot wagabundy, pisząc długaśne poemaciska w rodzaju Jadąc do ciebie. Wspominam sygnalnie tych autorów, gdyż obaj o Barańczaku mówili w sposób skrajnie różny.  ...  Z kolei Podsiadło złożył przepiękny hołd Barańczakowi, gdy jeden ze swoich najlepszych wierszy, czyli Konfesatę, poprzedził, rzecz jasna, jednym z najsłynniejszych, zaimkowych fragmentów z Barańczaka  ... 
doi:10.14746/pspsl.2019.36.3 fatcat:kem7sfapsnbrxhccsqxx7s6vtu

Od Mickiewicza do Masłowskiej: Adaptacje filmowe literatury polskiej [From Mickiewicz to Masłowska: Film adaptations of Polish literature]

Krzysztof Loska
2015 The Polish Review  
Krzysztof Loska Jagiellonian University . Jerzy Ziomek, Powinowactwa literatury: Studia i szkice (Warsaw: Państwowe Wydawnictwo Naukowe, 1980).  ...  refers to an alternative approach to Romanticism proposed by Agata Bielik-Robson in her book Romantyzm, niedokończony projekt (Romanticism, an unfinished project). 2 Also, the text written by Magdalena Podsiadło  ... 
doi:10.5406/polishreview.60.4.0103 fatcat:v6wasbztrzextpzom5xdh6r3sy

Źródła i rodzaje ryzyka w sektorze finansów publicznych

Ewelina Młodzik
2015 Prace Naukowe Uniwersytetu Ekonomicznego we Wrocławiu  
Poland ........ 87 Krystyna Kietlińska: The role of 1% of PIT and CIT in supporting charity organizations in Poland ............................................................................... 102 Krzysztof  ...  Poland ........... 181 Elwira Pindyk: Influence of development plan on the municipality's incomes for property tax from natural persons ......................................................... 192 Piotr Podsiadło  ... 
doi:10.15611/pn.2015.403.15 fatcat:vmgdjwusqbbzxhxnodxbyos53m

Par la porte dérobée: La poésie polonaise en français

Alice-Catherine Carls
2013 Archiwum Emigracji  
Christophe (Krzysztof Andrzej) Jeżewski est musicologue et poète, et il traduit aussi bien vers le polonais que vers le français. Peut-on, doit-on ne traduire que de la poésie?  ...  Il a pu faire publier des traductions des poètes polonais Zbigniew Herbert, Niemec, Podsiadło, Tomasz Rozycki.  ...  2012) et La Différence / Orphée (Aleksander Wat, 2013; Jarosław Iwaszkiewicz, 2015), les éditions Grèges ont publié un volume de poésies d'Urszula Kozioł en 2012 et préparent un volume de poésies de Krzysztof  ... 
doi:10.12775/ae.2013.003 fatcat:cuxw2u335jgnzlxaevospqs32y
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