59 research outputs found
From advanced materials to stretchable and biodegradable batteries
No full textAuthor Mahya Karamimosammam, MScDissertation Johannes Kepler Universität Linz 2025Arbeit nach Ablauf der Sperre auf den öffentlichen PCs in den Bibliotheken der JKU+Medizin abrufba
From advanced materials to stretchable and biodegradable batteries
No full textAuthor Mahya Karamimosammam, MScDissertation Johannes Kepler Universität Linz 2025Arbeit nach Ablauf der Sperre auf den öffentlichen PCs in den Bibliotheken der JKU+Medizin abrufba
Toward Real-Time Image Annotation Using Marginalized Coupled Dictionary Learning
No full textIn most image retrieval systems, images include various high-level semantics,
called tags or annotations. Virtually all the state-of-the-art image annotation
methods that handle imbalanced labeling are search-based techniques which are
time-consuming. In this paper, a novel coupled dictionary learning approach is
proposed to learn a limited number of visual prototypes and their corresponding
semantics simultaneously. This approach leads to a real-time image annotation
procedure. Another contribution of this paper is that utilizes a marginalized
loss function instead of the squared loss function that is inappropriate for
image annotation with imbalanced labels. We have employed a marginalized loss
function in our method to leverage a simple and effective method of prototype
updating. Meanwhile, we have introduced regularization on semantic
prototypes to preserve the sparse and imbalanced nature of labels in learned
semantic prototypes. Finally, comprehensive experimental results on various
datasets demonstrate the efficiency of the proposed method for image annotation
tasks in terms of accuracy and time. The reference implementation is publicly
available on https://github.com/hamid-amiri/MCDL-Image-Annotation.Comment: @article{roostaiyan2022toward, title={Toward real-time image
annotation using marginalized coupled dictionary learning},
author={Roostaiyan, Seyed Mahdi and Hosseini, Mohammad Mehdi and Kashani,
Mahya Mohammadi and Amiri, S Hamid}, journal={Journal of Real-Time Image
Processing}, volume={19}, number={3}, pages={623--638}, year={2022},
publisher={Springer}
Psychiatric Disease Susceptibility and Pain in Chronic Pancreatitis:Association or Causation?
No full textABSTRACT: Pain perception in chronic pancreatitis (CP) is governed by the transmission of nociceptive inputs into the pain processing centers of the brain. These regions of the brain overlap with those that regulate and process emotions and cognition. Disorders in these regions also result in psychiatric conditions such as depression, anxiety, and posttraumatic stress disorder. The present study by Dunbar et al. evaluated 24 single nucleotide polymorphisms associated with anxiety and/or posttraumatic stress disorder and found correlations with constant and severe pain phenotypes in CP patients from a large cross-sectional cohort study. Although causation cannot be proven, the findings suggest that there may be a role for neuromodulator drugs for the treatment of pain in CP based on individual genetic susceptibility.</p
EFFECTS OF POST-PRINTING HEAT TREATMENT AND ADDITION OF CERAMIC-BASED NANOPARTICLES ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF WIRE ARC ADDITIVE MANUFACTURED PH 13-8Mo MARTENSITIC STAINLESS STEEL
No full textThis thesis is prepared in a paper-based format, in which the stemmed journal papers on the WAAM processing of the PH 13-8Mo MSS are presented in chapters 2, 3, and 4, followed by overall conclusions and future works in chapter 5. In addition to the above chapters that cover the primary structure of this thesis, the author has been also involved in a few side projects during her Ph.D. program on the WAAM processing of low-carbon low-alloy steel (ER70S-6) and martensitic stainless steel (ER420) alloys, which are presented as appendices 1 and 2 at the end of this thesis. In total, as a result of the research activities during this Ph.D. program, 19 articles were published in or submitted to peer-reviewed journals (five articles as the first author and 14 articles as the co-author). Moreover, the thesis's outcomes were presented at different conferences (three papers as the first author and seven papers as the co-author).Precipitation hardening martensitic stainless steels offer an outstanding combination of strength and corrosion resistance under harsh environmental conditions while maintaining their moderate toughness. The reasonable weldability of these alloys makes them suitable candidates for wire arc additive manufacturing (WAAM) with a significant deposition rate, high material usage efficiency, and lower capital and fabrication costs as compared to traditional subtractive manufacturing methods. Aiming to accelerate the widespread adoption of this state-of-the-art manufacturing technology, in the first phase of this research, the fabrication feasibility of the PH 13-8Mo martensitic stainless steel through the WAAM was investigated. The obtained results proved the successful fabrication of a sound and defect-free PH 13-8Mo part with a great combination of hardness, ductility, and tensile strength. However, the complex thermal history experienced by different locations of the component caused a gradual increase of microhardness and ultimate tensile strength values along the building direction owing to the non-uniform distribution of residual δ-ferrite and retained austenite. Moreover, the intrinsic directional heat sink towards the substrate resulted in the formation of a columnar structure of primary δ-ferrite grains, leading to a strong cubic texture and anisotropy in ductility. To address this issue, in the second phase of the performed research, different post-printing heat treatment cycles, including solution and aging treatments at different temperatures, were applied on the additively manufactured PH 13-8Mo samples to modify the microstructural features, promote the equiaxed grain structure, eliminate the anisotropic behaviour, and improve the mechanical properties. It was revealed that the solution treatment at 1050 °C for 1 h resulted in the dissolution of undesired δ-ferrite and removal of the columnar structure and anisotropic ductility, while the following aging at 500 °C for 4 h led to the maximum hardness and tensile strength due to the formation of optimum sized β-NiAl precipitates in a fully martensitic matrix. Despite the benefits of post-printing heat treatment, it increases the lead time and cost of the fabrication process, which is contrary to the value proposition of WAAM technology. Thus, in the third phase of this research, the potential grain refinement and strengthening through the introduction of TiC and TiB2 reinforcing ceramic nanopowders into the molten pool during WAAM processing was investigated. Although both inoculant agents refined the columnar primary δ-ferrite grains and provoked the precipitation of in-situ hard TiC/M3B2 phases, TiB2 nanopowders were found to be a more effective grain refiner as compared to TiC reinforcing particles. Overall, the fabrication feasibility of PH 13-8Mo alloy via WAAM was validated, while further microstructural and mechanical properties improvement was accomplished through the implementation of appropriate post-printing heat treatment cycle or by the addition of TiC and TiB2 nanopowder inoculants during the deposition process
On amenability constants of Fourier algebras : new bounds and new examples
No full textLet be a locally compact group. If is finite then the amenability constant of its Fourier algebra, denoted by , admits an explicit formula [Johnson, JLMS 1994]; if is infinite then no such formula for is known, although lower and upper bounds were established by Runde [PAMS 2006]. Using non-abelian Fourier analysis, we obtain a sharper upper bound for when is discrete. Combining this with previous work of the first author [Choi, IMRN 2023], we exhibit new examples of discrete groups and compact groups where can be calculated explicitly; previously this was only known for groups that are products of finite groups with "degenerate"' cases. Our new examples also provide additional evidence to support the conjecture that Runde's lower bound for the amenability constant is in fact an equality
Neurocognitive, Mental Health, and Glucose Disorders in Farmers Exposed to Organophosphate Pesticides
No full textOko 25 milijuna zemljoradnika iz zemalja u razvoju imalo je barem jednu epizodu trovanja na godinu, uglavnom antikolinesteraznim organofosfatima. Cilj ovoga križnog ispitivanja bio je utvrditi u 187 profesionalno izloženih zemljoradnika toksično djelovanje organofosfata na neurokognitivnu funkciju, mentalno zdravlje, kliničke simptome, dijabetes i hematološke parametre. Izložena je skupina uspoređena s odgovarajućom kontrolnom skupinom od 187 ispitanika odgovarajuće dobi, spola i obrazovanja. Neurokognitivni poremećaj mjeren je s pomoću Inventara za subjektivnu procjenu neurokognitivne funkcije (izv. Subjective Neurocognition Inventory, krat. SNI), a mentalno zdravlje ocijenjeno s pomoću Upitnika o općem zdravstvenom stanju s 28 stavki (izv. General Health Questionnaire-28, krat. GHQ-28). Ispitanicima su također napravljene pretrage glukoze u krvi natašte (FBG), ureje u krvi (BUN), kolesterola (CL), triglicerida (TG), kreatinina, zatim test podnošljivosti oralne glukoze (GTT), lipoproteina visoke gustoće (HDL), aspartat aminotransferaze (AST), alanin aminotransferaze (ALT) i alkalne fosfataze (ALP). Izloženi zemljoradnici imali su značajno više nalaze FBG-a (pAbout 25 million agricultural workers in the developing world suffer from at least one episode of poisoningeach year, mainly by anticholinesterase-like organophosphates (OPs). The objective of this cross-sectional study was to establish the OP toxicity in 187 occupationally exposed farmers in terms of neurocognitive impairment, mental health status, clinical symptoms, diabetes, and haematological factors. The exposed group was compared to 187 healthy age-, sex-, and education-matching controls. Neurocognitive impairment was measured using the Subjective Neurocognition Inventory (SNI) and mental health status using the General Health Questionnaire-28 (GHQ-28). The subjects were also tested for fasting blood glucose (FBG), blood urea nitrogen (BUN), cholesterol (CL), triglycerides (TG), creatinine, oral glucose tolerance test (GTT), high-density lipoprotein (HDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The exposed farmers showed higher FBG (
Förekomsten av whiplashtrauma hos TMD patienter
No full textSyfte Syftet med litteraturöversikten var att beskriva förekomst av whiplashtrauma hos TMD patienter.
Metod En systematisk litteratursökning av PubMed, CochraneLibrary och Bandolier databaser genomfördes för artiklar publicerade från 1 januari 1966 till 11 november 2011. Den systematiska sökningen identifierade121 artiklar. Efter borttagning av brev till redaktion och författarinlägg, utfördes en initial screening av abstract på 108 artiklar. Efter den initiala screeningen lästes 32 artiklar i fulltext med tillämpning av inklusions- och exklusionskriterier. Två av författarna utvärderade den metodologiska kvaliteten på de inkluderade studierna.
Resultat Sex studier mötte inklusionskriterierna och inkluderades i rapporten. Den rapporterade förekomsten av whiplashtrauma hos TMD populationerna varierade mellan 8,4 % och 70 % (median 35 %). Förekomst av whiplashtrauma hos kontrollgrupperna varierade mellan 1,7 % och 18 %. TMD patienter med historik av whiplashtrauma rapporterade gravare TMD symptom och mer smärta jämfört med TMD patienter utan nackskada.
Konklusion Resultaten från denna litteraturöversikt visar en högre förekomst av whiplashtrauma hos TMD patienter vilket tyder på att whiplashtrauma kan vara en riskfaktor för TMD. Stora variationer sågs mellan de olika inkluderade studierna och i samtliga studier fanns också brister gällande diagnoskriterier. Sammantaget så gör dessa begränsningar det svårt att bedöma traumaförekomst hos TMD patienter och i vilken utsträckning whiplashskada kan bidra till utvecklingen av TMD. Fler väldesignade studier som använder tydligt definierade diagnostiska kriterier med hög reliabilitet och validitet som t.ex RDC/TMD behövs för att kunna dra en säkrare slutsats om TMD vid whiplashtrauma.Aim The aim ofthis systemic literature review was to describe the prevalence of whiplash trauma in TMD populations.
Method A systemic literature search of the PubMed, Cochrane Library and Bandolier databases was carried out for articles published from 1 January 1966 to 11 November 2011. This systemic search identified 121 articles. After exclusion of letters to editor and author replies, an initial screening of the abstracts of 108 articles was carried out. After the initial screening 32 articles were read in full text applying the inclusion and exclusion criteria. Two of the authors evaluated the methodological quality of the included studies.
Result Six studies matched the inclusion criteria and were included in the review. The reported prevalence of whiplash trauma in the TMD populations varied from 8.4% to 70% (median 35%). The prevalence of whiplash trauma in the control groups varied from1.7% to 18%.TMD patients with a history of whiplash trauma reported more TMD symptom and more pain compared to TMD patient without a neck injury.
Conclusion The results from this literature review show a higher prevalence of whiplash trauma in TMD patients which indicate that whiplash trauma could be risk factor for TMD. A large variation could be seen between the included studies and there were also weaknesses with regard to the diagnostic criteria. In summery we suggest that these limitations make it difficult to assess the prevalence of neck trauma in TMD patients and to which extent a whiplash injury can contribute to the development of TMD. More well designed studies using the RDC/TMD criteria and well-defined criteria with high reliability and validity for whiplash trauma are needed in order to make a more reliable conclusion
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