105 research outputs found
Diagnosis of concrete dams by flat-jack tests and inverse analyses based on proper orthogonal decomposition
No full textFlat-jack tests have been employed for decades for the assessment of stresses and Young moduli in possibly deteriorated concrete dams and masonry structures. We propose a procedure for such tests that includes several innovations: identification of Young moduli and shear modulus in the presence of orthotropy, of pre-existing normal and shear stresses, and of tensile and compressive strength and fracture energy; use of full-field displacement measurements by digital image correlation (instead of extensometers); computer simulations performed once-and-for-all and productive of results which are subsequently processed out by proper orthogonal decomposition and its truncation; and identification of parameters in situ, soon after the tests, by portable computer with software able to perform inverse analyses by mathematical tools newly introduced into this context. The proposed procedure is validated by means of pseudoexperimental numerical exercises, by employing comparatively, as central computational tools, artificial neural networks and a trust region algorithm implying only first-order derivatives (with respect to the sought parameters) of the discrepancy function to minimize
Philosophy of Tadeusz Garbowski
No full textThe period between the two World Wars was very fruitful for Polish philosophy. The best known intellectual formation of that time was the Lvov–Warsaw School of Logic. At the time, when members of that school philosophized in the context of logic and mathematics, there was a group of thinkers in Cracow, who attempted at creating a philosophy of nature. Unfortunately, because of the outbreak of the Second World War, they have never produced any philosophical school. One of the first of Cracow philosophers of nature was the biologist, Tadeusz Garbowski. He died in 1939 in Sachsenhausen concentration camp, leaving several philosophical papers which focus mostly on the theory of evolution. In the present paper, the author critically reviews his analyses. A lot of his ideas, e.g., the one called by the author the 'evolutionary epistemology', can be found in works of later thinkers, for instance in the works of Konrad Lorenz. Although it is doubtful that they actually knew Garbowski's papers, it still seems to be worthwhile to notice this historical fact
Diagnostic inverse structural analyses based on indentation curves alone and novel indenter geometries
No full textNon-destructive indentation tests are experiments with origin in hardness testing and at present of growing multiplicity of applications. The developments presented here (and at present research subjects in our team) are characterized by the following features: experimental data extracted only from indentation curves; novel indenter geometries optimized by sensitivity analyses; parameter identifications by a deterministic approach and by preliminary model reduction apt to make economical and fast the discrepancy minimization algorithm. The estimates provided by the innovative inverse analysis procedures concern: residual stresses or fracture parameters or parameters in anisotropic plasticity models
Optimised structural modelling for inverse analysis parameter identification relying on dynamic measurements.
No full textIn the context of Inverse Analysis in Civil Engineering, parameter identification and
model calibration, of a structural system, relying on dynamic measurements, are subjects of a
growing research interest. In the present contribution, the topic is tackled with reference both
to simplified structural numerical examples and to a specific case study, namely a historical
road three-span reinforced concrete arched bridge, with vibrational data previously acquired
by standard wired accelerometers on the deck, under operational traffic conditions. In particular, the present work aims at focussing on the identification issues, concerning the definition of a maximum allowable threshold number of sought material parameters (e.g., Young’s moduli and mass densities of different structural components), with respect to the amount of available measurement data, and the investigation of the inverse analysis discrepancy function to be optimised, in order to set the intrinsic issue of multiple “realizations”, in case of a plain use of modal properties, and in view of forming a well–posed optimisation problem. Structural modelling, sensitivity analysis and numerical optimisation approaches are herein combined toward a robust and efficient identification strategy, to be effectively employed in structural assessment and diagnosis, also with respect to originally available or enriched sets of experimental data.
The proposed methodology, and collected results, shall outline an efficient identification procedure, in view of automated inverse analysis, practically oriented to the dynamic assessment and structural diagnosis in the Civil Engineering context, as applied e.g. to strategic bridge infrastructures
Biopsy-based calibration of T2* magnetic resonance for estimation of liver iron concentration and comparison with R2 Ferriscan
No full textThere is a need to standardise non-invasive measurements of liver iron concentrations (LIC) so clear inferences can be drawn about body iron levels that are associated with hepatic and extra-hepatic complications of iron overload. Since the first demonstration of an inverse relationship between biopsy LIC and liver magnetic resonance (MR) using a proof-of-concept T2* sequence, MR technology has advanced dramatically with a shorter minimum echo-time, closer inter-echo spacing and constant repetition time. These important advances allow more accurate calculation of liver T2* especially in patients with high LIC
Pests or “Guerilla-fighters” of Cyberspace? An Attempt at a Typology of Internet Trolls
No full textArtykuł ma na celu przedstawienie propozycji kryteriów podziału poszczególnych
rodzajów użytkowników internetu zwanych potocznie oraz w literaturze fachowej
„internetowymi trollami”. Zawiera odniesienia do istniejących w polskim
obiegu naukowym publikacji, jak również poszerza zakres terminu, który odnosi
się przede wszystkim do prowokatorów obecnych w przestrzeni mediów społecznościowych,
ale także do hejterów, atencjuszy, czy spammerów. Autor porównuje
działania trolli internetowych do partyzantki, która wykorzystując niekonwencjonalne
metody walki przeciwstawia się, bądź konkuruje z odgórnie zorganizowanymi
strukturami oraz narzuconymi autorytetami.This article contains a proposal of criteria for the distinguishing various types of
internet users described colloquially as “internet trolls”. It not only includes references
to existing Polish academic publications but also broadens the scope of the
term, which relates mostly to provocatively acting persons within the realm of
social media and to haters, attention-seekers or spammers. The author compares
the activities of internet trolls to those of guerrilla-fighters who, with the aid of
non-conventional methods, either combat or compete with the established organized
structures or authorities imposed by them.Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00
Book Review: Anna Niedźwiedź and Kaja Kajder, eds., Mapy miasta: Dziedzictwa i sacrum w przestrzeni Krakowa / Maps of the City: Heritages and the Sacred within Kraków’s Cityscape.
No full textThe book Maps of the City is the result of an exhibition at The Seweryn Udziela Ethnographic Museum in Kraków that was held between November 2017 and February 2018. As the subtitle makes clear, the exhibition focused on the place of heritage and the sacred within Kraków’s cityscape, together with the relationship between the two, both for the city’s residents and visitors. The latter group includes pilgrims. The curator of the exhibition was Anna Niedźwiedź, a cultural anthropologist at Jagiellonian University and author of The Image and the Figure: Our Lady of Częstochowa in Polish Culture and Popular Religion (2010). She is also one of the editors of the book. This richly illustrated volume is no mere catalogue of a museum exhibition. The editors, together with their team of anthropologists, have written essays based on original research that forms the basis of the exhibition and the chapters of the book. What we have in the end is a book that is both for the broader reading public and the scholar, and due to its bilingual form, both for Polish and English readers
Linking changes in species composition and biomass in a globally distributed grassland experiment
No full textGlobal change drivers, such as anthropogenic nutrient inputs, are increasing globally. Nutrient deposition simultaneously alters plant biodiversity, species composition and ecosystem processes like aboveground biomass production. These changes are underpinned by species extinction, colonisation and shifting relative abundance. Here, we use the Price equation to quantify and link the contributions of species that are lost, gained or that persist to change in aboveground biomass in 59 experimental grassland sites. Under ambient (control) conditions, compositional and biomass turnover was high, and losses (i.e. local extinctions) were balanced
by gains (i.e. colonisation). Under fertilisation, the decline in species richness resulted from increased species loss and decreases in species gained. Biomass increase under fertilisation resulted mostly from species that persist and to a lesser extent from species gained. Drivers of ecological change can interact relatively independently with diversity, composition and ecosystem processes and functions such as aboveground biomass due to the individual contributions of species lost, gained or persisting.EEA Santa CruzFil: Ladouceur, Emma. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Ladouceur, Emma. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Ladouceur, Emma. University of Leipzig. Department of Biology; AlemaniaFil: Ladouceur, Emma. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Blowes, Shane A. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Blowes, Shane A. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Chase, Jonathan M. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Chase, Jonathan M. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Clark, Adam T. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Clark, Adam T. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Clark, Adam T. Karl-Franzens University of Graz. Institute of Biology; Austria.Fil: Garbowski, Magda. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Garbowski, Magda. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Alberti, Juan. Universidad Nacional de Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Laboratorio de Ecología. Mar del Plata; Argentina.Fil: Alberti, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Arnillas, Carlos Alberto. University of Toronto. Department of Physical and Environmental Sciences; Canadá.Fil: Bakker, Jonathan D. University of Washington. School of Environmental and Forest Sciences; Estados UnidosFil: Barrio, Isabel C. Agricultural University of Iceland. Faculty of Environmental and Forest Sciences; IslandiaFil: Bharath, Siddharth. Atria University; India.Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Harpole, Stanley. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Harpole, Stanley. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaMartin Luther University Halle-Wittenberg. Institute of Computer Science; Alemani
The War in Ukraine and Political Theology in Poland
No full textIn the broadest of terms, political theology can be defined as “the analysis of political arrangements (including cultural-psychological, social, and economic aspects) from the perspective of God’s ways with the world.”1 Since the world changes, as do the politics accompanying them, political theology is of necessity a dynamic branch of the theological enterprise. The editors to the second edition of The Wiley Blackwell Companion to Political Theology note a number of such changes that justify the expanded second edition of their handbook, including—what is most pertinent for understanding political theology at present in Poland—“the discourse on religion and violence, and new modalities of war.”2 A substantive chapter in this vein, by Emmanuel Katongole, starts with a news item concerning civil war in Ivory Coast in 2011. The author follows this sample news stressing the problems of “power struggle, corruption, sham elections, and civil war that characterize politics of much of sub-Saharan Africa.”3 Political theology is not new to Poland, but obviously the full- scale invasion by Russia of the neighboring Ukraine on February 24, 2022, together with the accompanying atrocities has had a similar impact in the field in the country to that of a number of the authors in the handbook. This article will provide an introductory view of a significant part of this ongoing response in the country
Topological Design of Machinery Base Plate for Minimum Vibration Transmission in a Lightweight Building (Keynote Lecture)
No full text- …
