4,023 results on '"A. Adamczak"'
Search Results
2. Exponential inequalities and laws of the iterated logarithm for multiple Poisson--Wiener integrals and Poisson $U$-statistics
- Author
-
Adamczak, Radosław and Kutek, Dominik
- Subjects
Mathematics - Probability ,Primary: 60E15, 60G55, 60F15. Secondary: 60D05, 05C80 - Abstract
We prove tail and moment inequalities for multiple stochastic integrals on the Poisson space and for Poisson $U$-statistics. We use them to demonstrate the Law of the Iterated Logarithm for these processes when the intensity of the Poisson process tends to infinity, with normalization depending on the degree of the multiple stochastic integral or degeneracy of the kernel defining the $U$-statistic. We apply our results to several classical functionals of Poisson point processes, obtaining improvements or complements of known concentration of measure results as well as new laws of the iterated logarithm. Examples include subgraph counts and power length functionals of geometric random graphs, intersections of Poisson $k$-flats, quadratic functionals of the Ornstein--Uhlenbeck L\'evy process and $U$-statistics of marked processes. Keywords: Poisson point process, $U$-statistics, multiple stochastic integrals, concentration of measure, The Law of the Iterated Logarithm
- Published
- 2024
3. The global and local limit of the continuous-time Mallows process
- Author
-
Adamczak, Radosław and Kotowski, Michał
- Subjects
Mathematics - Probability ,Mathematics - Combinatorics ,60C05, 60J27, 60J75, 05A05 - Abstract
Continuous-time Mallows processes are processes of random permutations of the set $\{1, \ldots, n\}$ whose marginal at time $t$ is the Mallows distribution with parameter $t$. Recently Corsini showed that there exists a unique Markov Mallows process whose left inversions are independent counting processes. We prove that this process admits a global and a local limit as $n \to \infty$. The global limit, obtained after suitably rescaling space and time, is an explicit stochastic process on $[0,1]$ whose description is based on the permuton limit of the Mallows distribution, analyzed by Starr. The local limit is a process of permutations of $\mathbb{Z}$ which is closely related to the construction of the Mallows distribution on permutations of $\mathbb{Z}$ due to Gnedin and Olshanski. Our results demonstrate an analogy between the asymptotic behavior of Mallows processes and the recently studied limiting properties of random sorting networks., Comment: 36 pages, 2 figures
- Published
- 2024
4. ADAR1 expression in different cancer cell lines and its change under heat shock
- Author
-
Adamczak, Dominika, Fornalik, Michał, Małkiewicz, Anna, Pestka, Julia, Pławski, Andrzej, Jagodziński, Paweł Piotr, and Słowikowski, Bartosz Kazimierz
- Published
- 2024
- Full Text
- View/download PDF
5. Investigating the Proton Structure: The FAMU experiment
- Author
-
Vacchi, A., Adamczak, A., Bakalov, D., Baldazzi, G., Baruzzo, M., Benocci, R., Bertoni, R., Bonesini, M., Cabrera, H., Carsi, S., Cirrincione, D., Chignoli, F., Clemenza, M., Colace, L., Danailov, M., Danev, P., de Bari, A., De Vecchi, C., De Vincenzi, M., Fasci, E., Gadedjisso-Tossou, K. S., Gianfrani, L., Hillier, A. D., Ishida, K., King, P. J. C., Maggi, V., Mazza, R., Menegolli, A., Mocchiutti, E., Moretti, L., Morgante, G., Niemela, J., Petroselli, C., Pizzolotto, C., Pullia, A., Ramponi, R., Roman, H. E., Rossella, M., Rossini, R., Sarkar, R., Sbrizzi, A., Stoilov, M., Stoychev, L., Suarez-Vargas, J. J., Toci, G., Tortora, L., Vallazza, E., Xiao, C., and Yokoyama, K.
- Subjects
Physics - Atomic Physics - Abstract
The article gives the motivations for the measurement of the hyperfine splitting (hfs) in the ground state of muonic hydrogen to explore the properties of the proton at low momentum transfer. It summarizes these proposed measurement methods and finally describes the FAMU experiment in more detail.
- Published
- 2024
- Full Text
- View/download PDF
6. Placental expression of GLUT‐1, GLUT‐3, and GLUT‐4 mRNA and transcriptome profiling in pregnant women with diabetes
- Author
-
Rafal Sibiak, Pawel Gutaj, Urszula Mantaj, Lukasz Adamczak, Malgorzata Blatkiewicz, Marcin Rucinski, and Ewa Wender‐Ozegowska
- Subjects
Glucose transporters ,Placenta ,Transcriptome ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
ABSTRACT Aims/Introduction Placental glucose transport is regulated by glucose transporter proteins (GLUTs). The study aimed to examine placental expression of GLUT‐1, GLUT‐3, and GLUT‐4 mRNA in patients with type 1 diabetes, early gestational diabetes (eGDM), and healthy controls, and to investigate correlations between GLUTs expression and clinical parameters. Additionally, we compared placental transcriptome profiles in recruited subgroups. Materials and Methods We recruited 59 pregnant women: 23 with type 1 diabetes, 17 with eGDM, and 19 controls. Patients with diabetes attended follow‐up visits at each trimester. Transcriptome studies were performed in 4 patients per subgroup. Results The mean age was similar across all subgroups. eGDM patients had significantly higher BMI and were predominantly obese. We observed a significant 2‐fold (P = 0.009) decrease in placental GLUT‐3 mRNA expression in the type 1 diabetes and eGDM groups. GLUT‐4 mRNA expression was significantly lower in the eGDM group compared to type 1 diabetes (3‐fold) and controls (6‐fold) (P = 0.007). There was a significant negative correlation between GLUT‐3 (R = −0.29) and GLUT‐4 (R = −0.27) mRNA expression and neonatal birth weight. GLUT‐4 expression was negatively correlated with 1st trimester HbA1c (R = −0.72) and OGTT 120′ (R = −0.82) results in eGDM patients, and 3rd trimester glycemic variability (R = −0.49) in type 1 diabetes. Microarray analysis revealed significant transcriptomic changes, with 45 down‐regulated and 365 up‐regulated genes in type 1 diabetes, and 21 significant changes in eGDM. Conclusions Placental samples from patients with diabetes exhibit changes in GLUTs expression, which correlates with neonatal growth and several glycemic parameters. Additionally, multiple changes in transcriptomic profiles are observed in hyperglycemic patients.
- Published
- 2025
- Full Text
- View/download PDF
7. Status of the detector setup for the FAMU experiment at RIKEN-RAL for a precision measurement of the Zemach radius of the proton in muonic hydrogen
- Author
-
Rossini, R., Adamczak, A., Bakalov, D., Baldazzi, G., Banfi, S., Baruzzo, M., Benocci, R., Bertoni, R., Bonesini, M., Bonvicini, V., Cabrera, H., Carsi, S., Cirrincione, D., Clemenza, M., Colace, L., Danailov, M. B., Danev, P., de Bari, A., de Vecchi, C., Fasci, E., Gadedjisso-Tossou, K. S., Gaigher, R., Gianfrani, L., Hillier, A. D., Ishida, K., King, P. J. C., Maggi, V., Menegolli, A., Mocchiutti, E., Moretti, L., Morgante, G., Niemela, J., Petroselli, C., Pirri, A., Pizzolotto, C., Prata, M. C., Pullia, A., Pullia, M., Ramponi, R., Rossella, M., Sarkar, R., Sbrizzi, A., Stoilov, M., Suarez-Vargas, J. J., Toci, G., Tortora, L., Vallazza, E. S., Yokoyama, K., and Vacchi, A.
- Subjects
Physics - Atomic Physics ,High Energy Physics - Experiment - Abstract
The FAMU experiment at RIKEN-RAL is a muonic atom experiment with the aim to determine the Zemach radius of the proton by measuring the 1s hyperfine splitting in muonic hydrogen. The activity of the FAMU Collaboration in the years 2015-2023 enabled the final optimisation of the detector-target setup as well as the gas working condition in terms of temperature, pressure and gas mixture composition. The experiment has started its data taking in July 2023. The status of the detector setup for the 2023 experimental runs, for the beam characterisation and muonic X-ray detection in the 100-200 keV energy range, is presented and discussed., Comment: Submitted to JINST
- Published
- 2023
- Full Text
- View/download PDF
8. On Orlicz spaces satisfying the Hoffmann-J{\o}rgensen inequality
- Author
-
Adamczak, Radosław and Kutek, Dominik
- Subjects
Mathematics - Probability ,Mathematics - Functional Analysis ,60E15, 60B11, 46E30 - Abstract
Building on Talagrand's proof of the Hoffmann-J{\o}rgensen inequality for $L_p$ spaces and its version for the exponential Orlicz spaces we provide a full characterization of Orlicz functions $\Psi$ for which an analogous inequality holds in the Orlicz space $L_\Psi(F)$, where $F$ is an arbitrary Banach space. As an application we present a characterization of Talagrand-type concentration inequality for suprema of empirical processes with envelope in $L_\Psi$ (equivalently for sums of independent $F$-valued random variables in $L_\Psi(F)$). This result generalizes in particular an inequality by the first-named author concerning exponentially integrable summands and a recent inequality due to Chamakh-Gobet-Liu on summands with $\beta$-heavy tails. Another corollary concerns concentration for convex functions of independent, unbounded random variables, generalizing recent results due to Klochkov-Zhivotovskiy and Sambale. We also obtain a corollary concerning boundedness in $L_\Psi(F)$ of partial sums of a series of independent random variables, generalizing the original result by Hoffmann-J{\o}rgensen.
- Published
- 2023
9. Assessment of indoor environmental comfort for individuals wearing face masks of different thickness
- Author
-
Łukasz Jan Orman, Luiza Dębska, Lidia Dąbek, Stanislav Honus, and Stanisław Adamczak
- Subjects
questionnaire study ,environmental comfort ,indoor environment ,Environmental protection ,TD169-171.8 - Abstract
The present paper experimentally analyses the subjective assessment of indoor environment comfort based on a questionnaire survey conducted in a climate chamber located at Kielce University of Technology (Poland), if two types of face masks are worn by the respondents: thin (medical) and thick (cotton-made) masks. Air temperature and relative humidity in the chamber ranged from around 19 to 28oC and 20 – 70%, respectively. Precise measurement of the microclimate parameters was obtained with a microclimate meter, which recorded air temperature and relative humidity at the moment of completing the questionnaires. The respondents were of similar age (22 – 31 years old) and wore two types of clothing during the experiments: summer and winter, which differed by thermal resistance. This value amounted to 0.5 clo for the summer outfit and 0.8 clo for the winter one.In total 960 questionnaires were analysed in the study. The results indicate that the increase in air temperature led to poorer overall comfort, while the largest comfort sensation was recorded for the most favourable thermal sensation range. In general, thicker masks provided lower overall comfort than thinner masks for all relative humidity values.
- Published
- 2024
- Full Text
- View/download PDF
10. Physical activity, gestational weight gain in obese patients with early gestational diabetes and the perinatal outcome – a randomised–controlled trial
- Author
-
Adamczak, Lukasz, Mantaj, Urszula, Sibiak, Rafał, Gutaj, Paweł, and Wender-Ozegowska, Ewa
- Published
- 2024
- Full Text
- View/download PDF
11. Investigation of thermal comfort under face masks wearing conditions in the smart building
- Author
-
Łukasz J. Orman, Luiza Dębska, Stanislav Honus, Norbert Radek, Stanisław Adamczak, and Natalia Siwczuk
- Subjects
heat transfer ,smart building ,thermal comfort ,thermal environment ,thermal sensations ,Engineering (General). Civil engineering (General) ,TA1-2040 ,City planning ,HT165.5-169.9 - Abstract
The paper analyses thermal comfort of people wearing face masks. The study took place in the selected classrooms of the smart building “Energis” located in Poland. In the experiments 100 respondents participated. They filled in the questionnaire forms, in which they expressed their subjective assessment of the indoor thermal environment. Simultaneously, measurements of the physical parameters within the rooms were performed with a microclimate meter. The results clearly show that the use of face masks influenced thermal sensations of the people - they felt warmer than without the face mask on (at the same air temperature). Moreover, the respondents who wore the masks indicated that the air was more humid in relation to the case when the masks are not applied. The comparison of the obtained actual thermal sensations of the respondents with the calculation results according to the thermal comfort model proved that the model was unable to properly predict thermal sensations of people wearing face masks.
- Published
- 2025
- Full Text
- View/download PDF
12. A Tale of Success: Embedding Remediation and Curricular Design
- Author
-
Joseph P. McCollum, William Adamczak, and James R. Nolan
- Abstract
This paper reports how high failure rates in the first quantitative course that college business majors take were significantly reduced by implementing course-embedded remediation. More specifically, this paper details our process for identifying students at risk, placing them in special sections of the first quantitative course, and adding an additional hour of application of course concepts which resulted in a statistically significant increase in pass rates. The study focused on the learning environment, the attitude of the student, the utility of the material and the role of the professor for this special course. We feel this research is timely, as many colleges in the United States consider removing entrance exams as a means of evaluation into higher education.
- Published
- 2022
13. Experimental determination of the energy dependence of the rate of the muon transfer reaction from muonic hydrogen to oxygen for collision energies up to 0.1 eV
- Author
-
Stoilov, M., Adamczak, A., Bakalov, D., Danev, P., Mocchiutti, E., Pizzolotto, C., Baldazzi, G., Baruzzo, M., Benocci, R., Bonesini, M., Cirrincione, D., Clemenza, M., Fuschino, F., Hillier, A. D., Ishida, K., King, P. J. C., Menegolli, A., Monzani, S., Ramponi, R., Rignanese, L. P., Sarkar, R., Sbrizzi, A., Tortora, L., Vallazza, E., and Vacchi, A.
- Subjects
Physics - Atomic Physics - Abstract
We report the first experimental determination of the collision-energy dependence of the muon transfer rate from the ground state of muonic hydrogen to oxygen at near-thermal energies. A sharp increase by nearly an order of magnitude in the energy range 0 - 70 meV was found that is not observed in other gases. The results set a reliable reference for quantum-mechanical calculations of low-energy processes with exotic atoms, and provide firm ground for the measurement of the hyperfine splitting in muonic hydrogen and the determination of the Zemach radius of the proton by the FAMU collaboration., Comment: 30 pages, 10 figures
- Published
- 2023
- Full Text
- View/download PDF
14. Adaptive cylindricity measurements with the use of circumferential section strategy
- Author
-
Janecki, Dariusz, Stępień, Krzysztof, and Adamczak, Stanisław
- Published
- 2024
- Full Text
- View/download PDF
15. Utilization of used textiles for solid recovered fuel production
- Author
-
Dziok, Tadeusz, Bury, Marcelina, Adamczak, Julia, Palka, Justyna, and Borovec, Karel
- Published
- 2024
- Full Text
- View/download PDF
16. Norms of structured random matrices
- Author
-
Adamczak, Radosław, Prochno, Joscha, Strzelecka, Marta, and Strzelecki, Michał
- Published
- 2024
- Full Text
- View/download PDF
17. Plant Use by the Funnel Beaker Farmers in Poland. New Archaeobotanical Data From Pottery Sherds and Daub Imprints
- Author
-
Dominika Kofel and Kamil Adamczak
- Subjects
archaeobotany ,imprints ,pottery ,daub ,neolithic ,fbc ,agriculture ,Archaeology ,CC1-960 - Abstract
The article presents the results of archaeobotanical studies on plant macroremains preserved both in charred form and as imprints in pottery and daub. The materials were collected from Funnel Beaker culture sites in Kałdus, Sławęcinek, Kietrz, and Małe Czyste. In total, 218 daub fragments and 33 pottery sherds were analysed. Most of the assemblages contained at least one of the searched items, such as imprints and/ or charred macroremains. Hulled wheat (Triticum monococcum/dicoccon/spelta) chaff, including glumes, glume bases, spikelet forks, and culms and blades of indeterminate cereals and/or wild grasses (Cerealia/Poaceae indet.), were among the most commonly found imprints. Interestingly, some assemblages contained crushed bones and microscopic charred wood fragments, illustrating a husbandry strategy that utilised all accessible resources.
- Published
- 2024
- Full Text
- View/download PDF
18. From intersection bodies to dual centroid bodies: a stochastic approach to isoperimetry
- Author
-
Adamczak, Radoslaw, Paouris, Grigoris, Pivovarov, Peter, and Simanjuntak, Paul
- Subjects
Mathematics - Metric Geometry ,Mathematics - Functional Analysis ,Mathematics - Probability ,Primary 52A21. Secondary 52A22, 52A38 - Abstract
We establish a family of isoperimetric inequalities for sets that interpolate between intersection bodies and dual Lp centroid bodies. This provides a bridge between the Busemann intersection inequality and the Lutwak--Zhang inequality. The approach depends on new empirical versions of these inequalities.
- Published
- 2022
19. Diffusion of muonic hydrogen in hydrogen gas and the measurement of the 1$s$ hyperfine splitting of muonic hydrogen
- Author
-
Nuber, J., Adamczak, A., Ahmed, M. Abdou, Affolter, L., Amaro, F. D., Amaro, P., Carvalho, P., Chang, Y. -H., Chen, T. -L., Chen, W. -L., Fernandes, L. M. P., Ferro, M., Goeldi, D., Graf, T., Guerra, M., Hänsch, T. W., Henriques, C. A. O., Hildebrandt, M., Indelicato, P., Kara, O., Kirch, K., Knecht, A., Kottmann, F., Liu, Y. -W., Machado, J., Marszalek, M., Mano, R. D. P., Monteiro, C. M. B., Nez, F., Ouf, A., Paul, N., Pohl, R., Rapisarda, E., Santos, J. M. F. dos, Santos, J. P., Silva, P. A. O. C., Sinkunaite, L., Shy, J. -T., Schuhmann, K., Rajamohanan, S., Soter, A., Sustelo, L., Taqqu, D., Wang, L. -B., Wauters, F., Yzombard, P., Zeyen, M., Zhang, J., and Antognini, A.
- Subjects
Physics - Atomic Physics ,High Energy Physics - Experiment - Abstract
The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ($\mu$p) with 1 ppm accuracy by means of pulsed laser spectroscopy. In the proposed experiment, the $\mu$p atom is excited by a laser pulse from the singlet to the triplet hyperfine sub-levels, and is quenched back to the singlet state by an inelastic collision with a H$_2$ molecule. The resulting increase of kinetic energy after this cycle modifies the $\mu$p atom diffusion in the hydrogen gas and the arrival time of the $\mu$p atoms at the target walls. This laser-induced modification of the arrival times is used to expose the atomic transition. In this paper we present the simulation of the $\mu$p diffusion in the H$_2$ gas which is at the core of the experimental scheme. These simulations have been implemented with the Geant4 framework by introducing various low-energy processes including the motion of the H$_2$ molecules, i.e. the effects related with the hydrogen target temperature. The simulations have been used to optimize the hydrogen target parameters (pressure, temperatures and thickness) and to estimate signal and background rates. These rates allow to estimate the maximum time needed to find the resonance and the statistical accuracy of the spectroscopy experiment., Comment: Submission to SciPost
- Published
- 2022
20. Factors Influencing the Effectiveness of Medical Products Stock Management in Polish Hospitals - Research Results
- Author
-
Gawronska, Anna, Kolinski, Adam, Adamczak, Michal, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Rocha, Alvaro, editor, Adeli, Hojjat, editor, Dzemyda, Gintautas, editor, Moreira, Fernando, editor, and Colla, Valentina, editor
- Published
- 2024
- Full Text
- View/download PDF
21. Multilingual Students’ Translingual Practices During Classes of English as a Foreign Language: Attitudes of Polish and German EFL Teachers
- Author
-
Hadrian Lankiewicz, Sylwia Adamczak-Krysztofowicz, and Grzegorz Lisek
- Subjects
Language and Literature - Abstract
This paper focuses on the challenges in educational area or, more precisely, we narrow down our considerations to the context of teaching English as a foreign language (EFL). Research on multilingualism points to the need for a heteroglossic approach to language use in educational process [García, Leiva 2014]. The aim of our research is to delve into the mindset of EFL teachers regarding (1) their acceptance of translingual practices during an EFL class taught to plurilinguals, (2) the articulation of potential benefi ts or drawbacks for the language learning process aff ected by translingual practices, and, ultimately, (3) the perception of these practices with reference to TCLA (teacher critical language awareness). The obtained data shows an interesting picture of teaching EFL in the multilingual context of mixed nationality students. Both Polish and German teachers of EFL seem to reach beyond the monolingual paradigm in the classroom. The majority of teachers can speak or understand additional languages to their native language and EFL. This may be construed as a potential for the strategic use of translanguaging for educational purposes and, ultimately, it is interpreted as a transformative quality of the language teacher in the education.
- Published
- 2024
- Full Text
- View/download PDF
22. Muonic atom spectroscopy with microgram target material
- Author
-
Adamczak, A., Antognini, A., Berger, N., Cocolios, T. E., Deokar, N., Düllmann, Ch. E., Eggenberger, A., Eichler, R., Heines, M., Hess, H., Indelicato, P., Kirch, K., Knecht, A., Krauth, J. J., Nuber, J., Ouf, A., Papa, A., Pohl, R., Rapisarda, E., Reiter, P., Ritjoho, N., Roccia, S., Seidlitz, M., Severijns, N., von Schoeler, K., Skawran, A., Vogiatzi, S. M., Warr, N., and Wauters, F.
- Subjects
Nuclear Experiment ,Physics - Atomic Physics - Abstract
Muonic atom spectroscopy -- the measurement of the x rays emitted during the formation process of a muonic atom -- has a long standing history in probing the shape and size of nuclei. In fact, almost all stable elements have been subject to muonic atom spectroscopy measurements and the absolute charge radii extracted from these measurements typically offer the highest accuracy available. However, so far only targets of at least a few hundred milligram could be used as it required to stop a muon beam directly in the target to form the muonic atom. We have developed a new method relying on repeated transfer reactions taking place inside a 100-bar hydrogen gas cell with an admixture of 0.25% deuterium that allows us to drastically reduce the amount of target material needed while still offering an adequate efficiency. Detailed simulations of the transfer reactions match the measured data, suggesting good understanding of the processes taking place inside the gas mixture. As a proof of principle we demonstrate the method with a measurement of the 2p-1s muonic x rays from a 5-{\mu}g gold target., Comment: 16 pages, 14 figures
- Published
- 2022
- Full Text
- View/download PDF
23. Growth in marine mammals: a review of growth patterns, composition and energy investment.
- Author
-
Adamczak, Stephanie, McHuron, Elizabeth, Christiansen, Fredrik, Dunkin, Robin, McMahon, Clive, Noren, Shawn, Pirotta, Enrico, Rosen, David, Sumich, James, and Costa, Daniel
- Subjects
body size ,growth ,marine mammal - Abstract
Growth of structural mass and energy reserves influences individual survival, reproductive success, population and species life history. Metrics of structural growth and energy storage of individuals are often used to assess population health and reproductive potential, which can inform conservation. However, the energetic costs of tissue deposition for structural growth and energy stores and their prioritization within bioenergetic budgets are poorly documented. This is particularly true across marine mammal species as resources are accumulated at sea, limiting the ability to measure energy allocation and prioritization. We reviewed the literature on marine mammal growth to summarize growth patterns, explore their tissue compositions, assess the energetic costs of depositing these tissues and explore the tradeoffs associated with growth. Generally, marine mammals exhibit logarithmic growth. This means that the energetic costs related to growth and tissue deposition are high for early postnatal animals, but small compared to the total energy budget as animals get older. Growth patterns can also change in response to resource availability, habitat and other energy demands, such that they can serve as an indicator of individual and population health. Composition of tissues remained consistent with respect to protein and water content across species; however, there was a high degree of variability in the lipid content of both muscle (0.1-74.3%) and blubber (0.4-97.9%) due to the use of lipids as energy storage. We found that relatively few well-studied species dominate the literature, leaving data gaps for entire taxa, such as beaked whales. The purpose of this review was to identify such gaps, to inform future research priorities and to improve our understanding of how marine mammals grow and the associated energetic costs.
- Published
- 2023
24. Innovative acoustic emission method for monitoring the quality and integrity of ferritic steel gas pipelines
- Author
-
Świt Grzegorz, Ulewicz Małgorzata, Pała Robert, Adamczak-Bugno Anna, Lipiec Sebastian, Krampikowska Aleksandra, and Dzioba Ihor
- Subjects
pipelines ,finite element method ,stress ,strain ,acoustic emission method ,Machine design and drawing ,TJ227-240 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
This article presents a comprehensive improvement in the experimental analysis of cracking processes in smooth and sharp V-notched samples taken from gas transport pipelines, utilizing the acoustic emission (AE) method. The research aimed to establish a robust correlation between the failure mechanisms of uni-axially tensile samples and the distinct characteristics of AE signals for enhanced quality management in pipeline integrity. The study encompassed materials from two different straight pipe sections, encompassing both long-term used materials and new, unused materials. Through the application of the k-means grouping method to AE signal analysis, we achieved the identification of AE signal parameters characteristic of various stages of the material destruction process. This advancement introduces a significant improvement in monitoring and managing the operational safety of pipeline networks, offering a methodology that leverages advanced acoustic emission signal analysis. The outcomes present significant implications for the pipeline industry by proposing methods to enhance safety systems and more effectively manage the integrity and quality of gas infrastructure.
- Published
- 2024
- Full Text
- View/download PDF
25. Limit theorems for the volumes of small codimensional random sections of $\ell_p^n$-balls
- Author
-
Adamczak, Radosław, Pivovarov, Peter, and Simanjuntak, Paul
- Subjects
Mathematics - Probability ,Mathematics - Functional Analysis ,Mathematics - Metric Geometry ,60D05, 52A22, 60F05 - Abstract
We establish Central Limit Theorems for the volumes of intersections of $B_{p}^n$ (the unit ball of $\ell_p^n$) with uniform random subspaces of codimension $d$ for fixed $d$ and $n\to \infty$. As a corollary we obtain higher order approximations for expected volumes, refining previous results by Koldobsky and Lifschitz and approximations obtained from the Eldan--Klartag version of CLT for convex bodies. We also obtain a Central Limit Theorem for the Minkowski functional of the intersection body of $B_p^n$, evaluated on a random vector distributed uniformly on the unit sphere., Comment: 32 pages
- Published
- 2022
26. Evaluation of the Variability of Vibration Measurement Results in Rolling Bearing Quality Control
- Author
-
Paweł Zmarzły, Mateusz Wrzochal, and Stanisław Adamczak
- Subjects
rolling bearings ,quality control ,industrial measurements ,vibration ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The final result of rolling bearing quality control is influenced by many factors that are not always taken into account. If non-conforming products leave the factory, then the reliability of equipment containing rolling bearings is significantly weakened. The paper presents an analysis of the reasons for the variability of vibration measurement results in rolling bearing quality control. The paper describes the organisation of rolling bearing acceptance inspection on the production line and its place in the rolling bearing production process. The study evaluates the influence of the measuring device and the location of the sensor on the result of the rolling bearing vibration monitoring process. The problem of repeatability and reproducibility of rolling bearing vibration measurement was also investigated. On the basis of the obtained results, conclusions were drawn regarding the improvement of the quality control process of rolling bearings in production plants.
- Published
- 2025
- Full Text
- View/download PDF
27. Factors Influencing the Effectiveness of Medical Products Stock Management in Polish Hospitals - Research Results
- Author
-
Gawronska, Anna, primary, Kolinski, Adam, additional, and Adamczak, Michal, additional
- Published
- 2024
- Full Text
- View/download PDF
28. Thermoregulation
- Author
-
Favilla, Arina B., primary, Adamczak, Stephanie K., additional, and Costa, Daniel P., additional
- Published
- 2024
- Full Text
- View/download PDF
29. Contributors
- Author
-
Adamczak, Stephanie K., primary, Adams, Danielle S., additional, Atkinson, Shannon, additional, Blawas, Ashley M., additional, Chris McKnight, J., additional, Cook, Peter F., additional, Costa, Daniel P., additional, Cozzi, Bruno, additional, Davis, Randall W., additional, De Guise, Sylvain, additional, Dujic, Zeljko, additional, Fahlman, Andreas, additional, Favilla, Arina B., additional, Fish, Frank E., additional, Gough, William T., additional, Hanke, Frederike D., additional, Hooker, Sascha K., additional, Huggenberger, Stefan, additional, Janik, Vincent M., additional, Kooyman, Gerald L., additional, Levin, Milton, additional, McDonald, Birgitte I., additional, Mooney, T. Aran, additional, Ortiz, Rudy M., additional, Patrician, Alexander, additional, Piscitelli-Doshkov, Marina, additional, Ponganis, Paul J., additional, Romano, Tracy A., additional, Somarelli, Jason A., additional, Suzuki, Miwa, additional, Thompson, Laura A., additional, Wells, Randall S., additional, and Williams, Terrie M., additional
- Published
- 2024
- Full Text
- View/download PDF
30. Radiocarbon dataset for the TRB central-place at Kałdus, Poland
- Author
-
Kamil Adamczak, Magdalena Kozicka, Łukasz Kowalski, Dominika Kofel, Wojciech Chudziak, Piotr Błędowski, Jacek Bojarski, Ryszard Kaźmierczak, and Marcin Weinkauf
- Subjects
14 C dating ,Bayesian modelling ,Late Neolithic ,Funnel beaker culture ,Baden culture ,Central Europe ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Science (General) ,Q1-390 - Abstract
This dataset compiles radiocarbon dates received for botanical macroremains and animal bones from domestic and ritual pits and human graves unearthed during excavations at the archaeological site of Kałdus (Poland) that can be related to the Funnel Beaker culture (TRB). Prior to radiocarbon dating by accelerator mass spectrometry (AMS), plant macroremains were checked against diagnostic attributes of species identification by standard paleobotanical analysis. The dataset contains already published (n = 4) and new (n = 10) radiocarbon dates that were used to establish the absolute chronology of the TRB habitus at Kałdus and its diachronic spatial organization. This dataset serves as an archive for future studies focusing on the TRB settlement pattern and organization in the region of modern Poland. It also has a utility to be reused in archaeological and chronological research on the movement of copper metalwork and the gradual spread of human cremation rite in the region.
- Published
- 2024
- Full Text
- View/download PDF
31. Laser excitation of the 1s-hyperfine transition in muonic hydrogen
- Author
-
Amaro, P., Adamczak, A., Ahmed, M. Abdou, Affolter, L., Amaro, F. D., Carvalho, P., Chen, T. -L., Fernandes, L. M. P., Ferro, M., Goeldi, D., Graf, T., Guerra, M., Hänsch, T. W., Henriques, C. A. O., Huang, Y. -C., Indelicato, P., Kara, O., Kirch, K., Knecht, A., Kottmann, F., Liu, Y. -W., Machado, J., Marszalek, M., Mano, R. D. P., Monteiro, C. M. B., Nez, F., Nuber, J., Ouf, A., Paul, N., Pohl, R., Rapisarda, E., Santos, J. M. F. dos, Santos, J. P., Silva, P. A. O. C., Sinkunaite, L., Shy, J. -T., Schuhmann, K., Rajamohanan, S., Soter, A., Sustelo, L., Taqqu, D., Wang, L. -B., Wauters, F., Yzombard, P., Zeyen, M., and Antognini, A.
- Subjects
Physics - Atomic Physics - Abstract
The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ($\mu$p) with 1 ppm accuracy by means of pulsed laser spectroscopy to determine the two-photon-exchange contribution with $2\times10^{-4}$ relative accuracy. In the proposed experiment, the $\mu$p atom undergoes a laser excitation from the singlet hyperfine state to the triplet hyperfine state, {then} is quenched back to the singlet state by an inelastic collision with a H$_2$ molecule. The resulting increase of kinetic energy after the collisional deexcitation is used as a signature of a successful laser transition between hyperfine states. In this paper, we calculate the combined probability that a $\mu$p atom initially in the singlet hyperfine state undergoes a laser excitation to the triplet state followed by a collisional-induced deexcitation back to the singlet state. This combined probability has been computed using the optical Bloch equations including the inelastic and elastic collisions. Omitting the decoherence effects caused by {the laser bandwidth and }collisions would overestimate the transition probability by more than a factor of two in the experimental conditions. Moreover, we also account for Doppler effects and provide the matrix element, the saturation fluence, the elastic and inelastic collision rates for the singlet and triplet states, and the resonance linewidth. This calculation thus quantifies one of the key unknowns of the HFS experiment, leading to a precise definition of the requirements for the laser system and to an optimization of the hydrogen gas target where $\mu$p is formed and the laser spectroscopy will occur., Comment: 21 pages, 4 figures
- Published
- 2021
- Full Text
- View/download PDF
32. The impact of electronic despatch advice on the service time of a means of transport in a distribution center
- Author
-
Marta Cudziło, Adam Koliński, Michał Adamczak, and Roman Domański
- Subjects
despatch advice ,supply chain digitization ,logistics operations ,Social Sciences ,Economics as a science ,HB71-74 - Abstract
Purpose: The aim of the article is to verify the impact of the use of electronic notification of deliveries on the service time of a means of transport in a distribution center. Methodology: The study used electronic notification in the form of EDI DESADV messages. The research was carried out in one of the distribution centers of a retail company operating in Poland. The study used the method of recording the time of logistics operations. The study was conducted in two stages (each lasting a week), in which the time of logistics operations was recorded in conditions without and with the DESADV message implemented. Results: The results of the conducted research show that the use of electronic despatch advice allows you to reduce the time of handling the means of transport in the distribution center. Conclusion: Reducing the time of handling the means of transport in the distribution center brings numerous additional benefits, such as faster release of the means of transport and enabling it to carry out subsequent transport tasks, handling a larger number of unloadings with the same number of resources (e.g. warehouse ramps), accelerating the internal process and enabling faster reloading to other means of transport performing the distribution process.
- Published
- 2024
- Full Text
- View/download PDF
33. Diagnosis of cardiovascular disease in patients with chronic kidney disease
- Author
-
Zoccali, Carmine, Mark, Patrick B., Sarafidis, Pantelis, Agarwal, Rajiv, Adamczak, Marcin, Bueno de Oliveira, Rodrigo, Massy, Ziad A., Kotanko, Peter, Ferro, Charles J., Wanner, Christoph, Burnier, Michel, Vanholder, Raymond, Mallamaci, Francesca, and Wiecek, Andrzej
- Published
- 2023
- Full Text
- View/download PDF
34. Concentration inequalities for some negatively dependent binary random variables
- Author
-
Adamczak, Radosław and Polaczyk, Bartłomiej
- Subjects
Mathematics - Probability ,60E15, 60B20, 60J28 - Abstract
We investigate concentration properties of functions of random vectors with values in the discrete cube, satisfying the stochastic covering property (SCP) or the strong Rayleigh property (SRP). Our result for SCP measures include subgaussian inequalities of bounded-difference type extending classical results by Pemantle and Peres and their counterparts for matrix-valued setting strengthening recent estimates by Aoun, Banna and Youssef. Under a stronger assumption of the SRP we obtain Bernstein-type inequalities for matrix-valued functions, generalizing recent bounds for linear combinations of positive definite matrices due to Kyng and Song. We also treat in detail the special case of independent Bernoulli random variables conditioned on their sum for which we obtain strengthened estimates, deriving in particular modified log-Sobolev inequalities, Talagrand's convex distance inequality and, as corollaries, concentration results for convex functions and polynomials, as well as improved estimates for matrix-valued functions. These results generalize inequalities for the uniform measure on slices of the discrete cube, studied extensively by many authors. Our approach is based on recent results by Hermon and Salez and a general framework involving modified log-Sobolev inequalities on the discrete cube, which is of independent interest.
- Published
- 2021
35. Measurement of the muon transfer rate from muonic hydrogen to oxygen in the range 70-336 K
- Author
-
Pizzolotto, C., Sbrizzi, A., Adamczak, A., Bakalov, D., Baldazzi, G., Baruzzo, M., Benocci, R., Bertoni, R., Bonesini, M., Cabrera, H., Cirrincione, D., Clemenza, M., Colace, L., Danailov, M., Danev, P., de Bari, A., De Vecchio, C., De Vincenzi, M., Fasci, E., Fuschino, F., Gadedjisso-Tossou, K. S., Gianfrani, L., Ishida, K., Labanti, C., Maggi, V., Mazza, R., Menegolli, A., Mocchiutti, E., Monzani, S., Moretti, L., Morgante, G., Niemela, J., Pullia, A., Ramponi, R., Rignanese, L. P., Rossella, M., Stoilov, M., Stoychev, L., Suarez-Vargas, J. J., Tortora, L., Vallazza, E., and Vacchi, A.
- Subjects
Physics - Atomic Physics - Abstract
The first measurement of the temperature dependence of the muon transfer rate from muonic hydrogen to oxygen was performed by the FAMU collaboration in 2016. The results provide evidence that the transfer rate rises with the temperature in the range 104-300 K. This paper presents the results of the experiment done in 2018 to extend the measurements towards lower (70 K) and higher (336 K) temperatures. The 2018 results confirm the temperature dependence of the muon transfer rate observed in 2016 and sets firm ground for comparison with the theoretical predictions.
- Published
- 2021
- Full Text
- View/download PDF
36. The Relationship of Creativity and Motor Creativity with Physical Activity and Motor Fitness in a Gender Perspective Among 8–9-Year-Old Children
- Author
-
Maryna Khorkova, Łukasz Bojkowski, Agata Korcz, Marlena Łopatka, Dagny Adamczak, Jana Krzysztoszek, and Michał Bronikowski
- Subjects
early education children ,motor creativity ,fitness ,sex differences ,physical education ,Pediatrics ,RJ1-570 - Abstract
Background: In this study, we aimed to determine the presence of any potential gender differences and relationships in terms of creativity, physical activity (PA), motor fitness, and motor creativity in children aged 8–9 years. Methods: The study included 195 primary school children (92 girls and 103 boys) aged 8–9 years old from grade 2. To determine creativity, the Test for Creative Thinking-Drawing Production was used, while motor creativity was assessed using Torrance’s ‘Thinking Creatively in Action and Movement’ test. Motor fitness was assessed with the selected items from the Eurofit battery and Piórkowski tests. The level of moderate-to-vigorous PA was determined with the Physical Activity Screening Measure. The Mann–Whitney U test was employed for in-between group comparison and Spearman’s correlation to determine relationships between the variables. Results: The results of the research showed the presence of differences in motor fitness between boys and girls, but no differences in PA, creativity, as well as motor creativity between genders. Moreover, it was found there was no association between PA and motor fitness and creativity or motor creativity in either boys or girls at this age. Conclusions: Thus, it can be assumed that to develop creativity through PA in children aged 8–9 years, it might be necessary to create an appropriate environment and strategy that will strengthen, inspire, and promote children’s creativity through movement. Having established that there is no difference in creativity between genders at this age, it was pointed out that it is necessary to look for teaching methods that would effectively awaken this ability in a co-educational setting.
- Published
- 2024
- Full Text
- View/download PDF
37. Fungal Biostarter and Bacterial Occurrence of Dry-Aged Beef: The Sensory Quality and Volatile Aroma Compounds after 21 Days of Aging
- Author
-
Wiesław Przybylski, Danuta Jaworska, Paweł Kresa, Grzegorz Ostrowski, Magdalena Płecha, Dorota Korsak, Dorota Derewiaka, Lech Adamczak, Urszula Siekierko, and Julia Pawłowska
- Subjects
dry-aged beef (DAB) ,Mucor flavus ,sensory quality ,volatile compounds ,microbiological quality ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this study, we decided to test the hypothesis that the fungal biostarter M. flavus used during a 21-day beef dry-aging process significantly impacts the composition of other microorganisms, the profile of volatile compounds, meat hardness characteristics, and, consequently, the sensory quality. The experiments were performed on samples derived from animals crossbred between Holstein–Fresian cows and meat breed bulls. Two groups of samples were studied, including the control group, without biostarter, and a group inoculated with the M. flavus biostarter. Both sample groups were seasoned for 21 days in the dry-aging fridge. The physicochemical parameters (pH, color parameters), the chemical composition of muscle, the determination of the shear force, the profile of volatile compounds (VOCs), and the sensory quality were evaluated after aging. During this study, classical microbiological methods were used to investigate the influence of fungal biostarters on the growth and survival of bacteria and other fungi (e.g., yeasts) during the dry-aging process of beef (DAB). The M. flavus biostarter improved the sensory quality of DAB, allowing high sensory quality to be achieved after just 21 days. This is likely due to the diverse VOCs produced by the fungus, including 1-tetradecanol, 2-nonenal, trans-2-undecenoic acid, and the following esters: formic acid hexyl ester, 10-undecenoic acid methyl ester, and 4-methylpentanoic acid methyl ester. The presence of the biostarter had no significant effect on the number of the bacteria or the survivability of the L. monocytogenes on the meat’s surface in laboratory conditions.
- Published
- 2024
- Full Text
- View/download PDF
38. Experimental-numerical analysis of the fracture process in smooth and notched V specimens
- Author
-
Świt Grzegorz, Dzioba Ihor, Ulewicz Małgorzata, Lipiec Sebastian, Adamczak-Bugno Anna, and Krampikowska Aleksandra
- Subjects
pipelines ,finite element method ,stress ,strain ,tresca criterion ,Machine design and drawing ,TJ227-240 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
This paper presents the outcomes of quality tests conducted on specimens, both smooth and V-notched, subjected to uniaxial tension, which were extracted from a gas transport pipeline. The introduction of the V-notch introduced variations in the stress and strain component fields near the plane of maximum constriction, consequently leading to their failure through different mechanisms. The process included the implementation of quality management practices such as numerical modeling and simulation of the loading of the specimens using ABAQUS. The material model employed in these calculations was defined and verified to ensure quality control. Subsequent to the numerical calculations, maps of the stress and strain component fields were generated, contributing to the quality assessment of the specimens. It was determined that the quality management process for the smooth specimen identifies the initiation of failure primarily due to the normal stress component in the central region of the plane with the largest constriction. In contrast, in the V-notched specimen, quality management efforts revealed that failure initiation occurs due to the tangential stress component, and failure proceeds through the shear mechanism. These results are valuable in developing a quality-driven methodology for monitoring the operational safety of gas network pipelines, primarily based on the analysis of acoustic emission signals.
- Published
- 2023
- Full Text
- View/download PDF
39. PHYSICAL ACTIVITY OF UKRAINIAN AND POLISH MEDICAL STUDENTS IN THE BEGINNING OF THE WAR IN UKRAINE
- Author
-
Bartosz Adamczak, Zofia Kuźnik, Szymon Makles, and Aureliusz Kosendiak
- Subjects
armed conflicts ,ukraine ,physical activity ,poland ,students ,Medicine - Published
- 2023
- Full Text
- View/download PDF
40. Reden wir über Geld!
- Author
-
Brohn, Sebastian, primary and Adamczak, Bini, additional
- Published
- 2023
- Full Text
- View/download PDF
41. Faktorenkomplexion und Methodenvielfalt in der empirischen Unterrichtsforschung in Deutsch als Fremd- und Zweitsprache – Einleitung in den Band
- Author
-
Adamczak-Krysztofowicz, Sylwia, primary, Ciepielewska-Kaczmarek, Luiza, additional, Jentges, Sabine, additional, Knopp, Eva, additional, Lazovic, Milica, additional, and Siebold, Kathrin, additional
- Published
- 2023
- Full Text
- View/download PDF
42. Modified log-Sobolev inequalities, Beckner inequalities and moment estimates
- Author
-
Adamczak, Radosław, Polaczyk, Bartłomiej, and Strzelecki, Michał
- Subjects
Mathematics - Probability ,Mathematics - Functional Analysis ,60E15 (Primary) 60J25, 60J27, 46E35, 46E39 (Secondary) - Abstract
We prove that in the context of general Markov semigroups Beckner inequalities with constants separated from zero as $p\to 1^+$ are equivalent to the modified log Sobolev inequality (previously only one implication was known to hold in this generality). Further, by adapting an argument by Boucheron et al. we derive Sobolev type moment estimates which hold under these functional inequalities. We illustrate our results with applications to concentration of measure estimates (also of higher order, beyond the case of Lipschitz functions) for various stochastic models, including random permutations, zero-range processes, strong Rayleigh measures, exponential random graphs, and geometric functionals on the Poisson path space., Comment: 56 pages, 1 figure; presentation in Sec. 4.7 changed
- Published
- 2020
- Full Text
- View/download PDF
43. Anti-racist interventions to transform ecology, evolution and conservation biology departments.
- Author
-
Cronin, Melissa R, Alonzo, Suzanne H, Adamczak, Stephanie K, Baker, D Nevé, Beltran, Roxanne S, Borker, Abraham L, Favilla, Arina B, Gatins, Remy, Goetz, Laura C, Hack, Nicole, Harenčár, Julia G, Howard, Elizabeth A, Kustra, Matthew C, Maguiña, Rossana, Martinez-Estevez, Lourdes, Mehta, Rita S, Parker, Ingrid M, Reid, Kyle, Roberts, May B, Shirazi, Sabrina B, Tatom-Naecker, Theresa-Anne M, Voss, Kelley M, Willis-Norton, Ellen, Vadakan, Bee, Valenzuela-Toro, Ana M, and Zavaleta, Erika S
- Subjects
Humans ,Ecology ,Engineering ,Population Groups ,Racism ,Black or African American ,Quality Education - Abstract
Racial and ethnic discrimination persist in science, technology, engineering and mathematics fields, including ecology, evolution and conservation biology (EECB) and related disciplines. Marginalization and oppression as a result of institutional and structural racism continue to create barriers to inclusion for Black people, Indigenous people and people of colour (BIPOC), and remnants of historic racist policies and pseudoscientific theories continue to plague these fields. Many academic EECB departments seek concrete ways to improve the climate and implement anti-racist policies in their teaching, training and research activities. We present a toolkit of evidence-based interventions for academic EECB departments to foster anti-racism in three areas: in the classroom; within research laboratories; and department wide. To spark restorative discussion and action in these areas, we summarize EECB's racist and ethnocentric histories, as well as current systemic problems that marginalize non-white groups. Finally, we present ways that EECB departments can collectively address shortcomings in equity and inclusion by implementing anti-racism, and provide a positive model for other departments and disciplines.
- Published
- 2021
44. Production culture, interpersonal relations, and the internationalisation of filmmaking industry
- Author
-
Balcerak, Malwina, primary, Stachowiak, Krzysztof, additional, and Adamczak, Marcin, additional
- Published
- 2023
- Full Text
- View/download PDF
45. Why is TASK Quarterly a Significant Journal to Publish Your Article? — A Bibliometric Analysis of a Scientific and Technical Journal
- Author
-
Beata Adamczak
- Subjects
publications ,citations ,bibliometric analysis ,Information technology ,T58.5-58.64 - Abstract
A bibliometric analysis of TASK Quarterly in the years 1997-2021 in terms of various bibliometric indicators was performed to celebrate the 25th anniversary of the publication of the first issue of the journal. The number of publications and citations increased over the mentioned span of years. The leading countries in terms of the greatest number of papers published in TASK Quarterly are Poland, Italy, Germany, Ukraine, USA and Russia. Moreover, it is shown that international collaboration can result in a greater number of citations per publication. The average publication time in TASK Quarterly is 77 days, including the average submission-acceptance time (44 days) and the average acceptancepublication time (33 days). Based on the author’s findings, it can be seen that although TASK Quarterly is a journal devoted mainly to physical and computer sciences, many publications also focus on the aspects related to mathematics, biomedical engineering and biophysics. CFD, molecular dynamics, the finite element method (FEM) and numerical simulations are the most frequently used keywords in articles published in TASK Quarterly.
- Published
- 2024
- Full Text
- View/download PDF
46. Moments of Gaussian chaoses in Banach spaces
- Author
-
Adamczak, Radosław, Latała, Rafał, and Meller, Rafał
- Subjects
Mathematics - Probability - Abstract
We derive moment and tail estimates for Gaussian chaoses of arbitrary order with values in Banach spaces. We formulate a conjecture regarding two-sided estimates and show that it holds in a certain class of Banach spaces including L_q spaces. As a corollary we obtain two-sided bounds for moments of chaoses with values in L_q spaces based on exponential random variables.
- Published
- 2020
- Full Text
- View/download PDF
47. Lubricating Performance of Polymer-Coated Liposomes
- Author
-
Hiorth, Marianne, Mihailovic, Ljubica, Adamczak, Malgorzata, Goycoolea, Francisco M., and Sarkar, Anwesha
- Published
- 2023
- Full Text
- View/download PDF
48. Indacenodithiophene homopolymers via direct arylation: direct polycondensation versus polymer analogous reaction pathways
- Author
-
Adamczak, Desiree, Komber, Hartmut, Illy, Anna, Scaccabarozzi, Alberto D., Caironi, Mario, and Sommer, Michael
- Subjects
Physics - Applied Physics ,Condensed Matter - Materials Science - Abstract
Indacenodithiophene (IDT) based materials are emerging high performance conjugated polymers for use in efficient organic photovoltaics and transistors. However, their preparation generally suffers from long reaction sequences and is often accomplished using disadvantageous Stille couplings. Herein, we present detailed synthesis pathways to IDT homopolymers using C-H activation for all C-C coupling steps. Polyketones are first prepared by direct arylation polycondensation (DAP) in quantitative yield and further cyclized polymer analogously. This protocol is suitable for obtaining structurally well-defined IDT homopolymers, provided that the conditions for cyclization are chosen appropriately and that side reactions are suppressed. Moreover, this polymer analogous pathway gives rise to asymmetric side chain patterns, which allows to fine tune physical properties. Alternatively, IDT homopolymers can be obtained via oxidative direct arylation polycondensation of IDT monomers (oxDAP), leading to IDT homopolymers with similar properties but at reduced yield. Detailed characterization by NMR, IR, UV-vis and PL spectroscopy, and thermal properties, is used to guide synthesis and to explain varying field-effect transistor hole mobilities in the range of 10-6- 10-3 cm2/Vs.
- Published
- 2019
- Full Text
- View/download PDF
49. On almost sure convergence of random variables with finite chaos decomposition
- Author
-
Adamczak, Radosław
- Subjects
Mathematics - Probability ,Mathematics - Functional Analysis ,60F99, 60H05, 60B11 - Abstract
Under mild conditions on a family of independent random variables $(X_n)$ we prove that almost sure convergence of a sequence of tetrahedral polynomial chaoses of uniformly bounded degrees in the variables $(X_n)$ implies the almost sure convergence of their homogeneous parts. This generalizes a recent result due to Poly and Zheng obtained under stronger integrability conditions. In particular for i.i.d. sequences we provide a simple necessary and sufficient condition for this property to hold. We also discuss similar phenomena for sums of multiple stochastic integrals with respect to Poisson processes, answering a question by Poly and Zheng., Comment: A few typos corrected
- Published
- 2019
50. Session-Based Hotel Recommendations: Challenges and Future Directions
- Author
-
Adamczak, Jens, Leyson, Gerard-Paul, Knees, Peter, Deldjoo, Yashar, Moghaddam, Farshad Bakhshandegan, Neidhardt, Julia, Wörndl, Wolfgang, and Monreal, Philipp
- Subjects
Computer Science - Information Retrieval - Abstract
In the year 2019, the Recommender Systems Challenge deals with a real-world task from the area of e-tourism for the first time, namely the recommendation of hotels in booking sessions. In this context, this article aims at identifying and investigating what we believe are important domain-specific challenges recommendation systems research in hotel search is facing, from both academic and industry perspectives. We focus on three main challenges, namely dealing with (1) multiple stakeholders and value-awareness in recommendations, (2) sparsity of user data and the extensive cold-start problem, and (3) dynamic input data and computational requirements. To this end, we review the state of the art toward solving these challenges and discuss shortcomings. We detail possible future directions and visions we contemplate for the further evolution of the field. This article should, therefore, serve two purposes: giving the interested reader an overview of current challenges in the field and inspiring new approaches for the ACM Recommender Systems Challenge 2019 and beyond.
- Published
- 2019
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.