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Kenan Turbic, Mariella Särestöniemi, M. Hämäläinen, L. Correia

This article investigates the impact of the user’s body on wearable antenna radiation characteristics and the consequent effects on the off-body channel, with the focus on the polarization aspect. The impact on antenna gain and polarization is analyzed for different antenna placements and separations from the body, based on electromagnetic simulations with numerical phantoms at 3, 4 and 5 GHz. Results show a strong influence of the body on the antenna efficiency, gain, and polarization. The excess losses due to body-shadowing suppress the antenna radiation behind the body by more than 20 dB, while its polarization changes from vertical in free space, to an elliptical one when placed on the body. The obtained radiation characteristics are then employed for off-body channel simulations using a geometry-based polarized channel model, which employs an analytic mobility model for wearable antennas based on Fourier series. The antenna rotation due to changes in user’s posture is seen as one of the main sources of off-body channel degradation. The polarization mismatch losses imposed by antennas’ physical misalignment, are observed to yield periodic fades of the Line-of-Sight component, with more than 30 dB drops in the received power level.

E. Alickovic, T. Lunner, D. Wendt, L. Fiedler, R. Hietkamp, E. Ng, C. Graversen

Objectives Selectively attending to a target talker while ignoring multiple interferers (competing talkers and background noise) is more difficult for hearing-impaired (HI) individuals compared to normal-hearing (NH) listeners. Such tasks also become more difficult as background noise levels increase. To overcome these difficulties, hearing aids (HAs) offer noise reduction (NR) schemes. The objective of this study was to investigate the effect of NR processing (inactive, where the NR feature was switched off, vs. active, where the NR feature was switched on) on the neural representation of speech envelopes across two different background noise levels [+3 dB signal-to-noise ratio (SNR) and +8 dB SNR] by using a stimulus reconstruction (SR) method. Design To explore how NR processing supports the listeners’ selective auditory attention, we recruited 22 HI participants fitted with HAs. To investigate the interplay between NR schemes, background noise, and neural representation of the speech envelopes, we used electroencephalography (EEG). The participants were instructed to listen to a target talker in front while ignoring a competing talker in front in the presence of multi-talker background babble noise. Results The results show that the neural representation of the attended speech envelope was enhanced by the active NR scheme for both background noise levels. The neural representation of the attended speech envelope at lower (+3 dB) SNR was shifted, approximately by 5 dB, toward the higher (+8 dB) SNR when the NR scheme was turned on. The neural representation of the ignored speech envelope was modulated by the NR scheme and was mostly enhanced in the conditions with more background noise. The neural representation of the background noise was modulated (i.e., reduced) by the NR scheme and was significantly reduced in the conditions with more background noise. The neural representation of the net sum of the ignored acoustic scene (ignored talker and background babble) was not modulated by the NR scheme but was significantly reduced in the conditions with a reduced level of background noise. Taken together, we showed that the active NR scheme enhanced the neural representation of both the attended and the ignored speakers and reduced the neural representation of background noise, while the net sum of the ignored acoustic scene was not enhanced. Conclusion Altogether our results support the hypothesis that the NR schemes in HAs serve to enhance the neural representation of speech and reduce the neural representation of background noise during a selective attention task. We contend that these results provide a neural index that could be useful for assessing the effects of HAs on auditory and cognitive processing in HI populations.

Nedim Jukić, S. Tomić, Rade Gašić

Tokom 2019. godine u granicama obuhvata Parka prirode “Orjen” realizovana su višestruka mikološka istraživanja s ciljem inventarizacije gljiva na ovom području. Među rezultatima istraživanja registrovan je i značajan broj pripadnika odjeljka Ascomycota od kojih su neke vrste po prvi put zabilježene na teritoriji Bosne i Hercegovine. U radu je prezentovan preliminarni spisak zabilježenih vrsta odjeljka Ascomycota dok su neke od vrsta (Desmazierella acicola, Bryoscyphus rhytidiadelphi, Pseudombrophila ripensis i Thecotheus keithii) detaljnije obrađene, uključujući njihovu ekologiju, fenologiju, morfološke karakteristike, poznate obrasce distribucije te eventualne egzistirajuće i potencijalne prijetnje na ovom području.

S obzirom na to da je šumarstvo djelatnost u kojoj su radnici izloženi relativno velikom stepenu opasnosti od nastanka povreda i profesionalnih oboljenja, ova pojava zahtijeva poseban pristup u segmentu zaštite na radu. Učestalost pojavljivanja povreda i profesionalnih oboljenja u šumarstvu dobar su pokazatelj nivoa sigurnosti radnika pri radu. Iz tog razloga se kroz analizu povreda na radu u JP ŠPD „Unskosanske šume” d.o.o. Bosanska Krupa nastojalo steći uvid u stanje sigurnosti na radu. Analiziran je period od 10 godina (2010–2019) i u tom periodu je evidentirano 213 povreda za cijelo preduzeće. Analiza povreda je obavljena po godinama i mjesecima, prema mjestu nastanka, prema radnom mjestu, prema materijalnom izvoru povrede, prema starosnoj dobi radnika, prema povrijeđenom dijelu tijela, itd. Na osnovu broja povreda po zapremini izrađenoga drveta (43/mil.m3), stanje sigurnosti pri radu može se ocijeniti kao zadovoljavajuće. Najzastupljenije su povrede ekstremiteta (64%), zatim, povrede su češće početkom radne sedmice (26,3%). Najčešći uzrok povrede bio je izazvan padom (62%). Analiza broja povreda po godinama u analiziranom periodu pokazuje da se ističu 2018, a naročito 2019. godina, što se može povezati sa trendom povećanja obima poslova u vlastitoj režiji. Takođe, analiza je pokazala da se najviše povreda desi u ljetnim mjesecima. Prema analizi koja se odnosi na invalide rada, ustanovljeno je da većina registrovanih invalida rada u preduzeću spada u invalide druge kategorije. Invalidi rada čine čak 10,36% ukupne radne snage. Za skoro 80% invalida rada kao glavni uzrok invalidnosti navedena je bolest, tj. razne zdravstvene tegobe koje su smanjile njihovu radnu sposobnost. Samo dvojica radnika su invalidi zbog profesionalnog oboljenja, što je veoma ohrabrujući podatak. Bez obzira na značajan tehnološki napredak i razvoj, posao u šumarstvu se još uvijek smatra jednim od najopasnijih zanimanja na svijetu.

A. Blagojevic, Željko Stević, D. Marinković, Sandra Kasalica, S. Rajilic

The conditions of globalization often dictate the functioning of transport markets, so it is necessary to conduct frequent research in order to achieve sustainable business. This is achieved through adequate risk and safety management at all levels. The research carried out in this paper includes determining the state of railway traffic safety in a total of nine railway sections in Bosnia and Herzegovina (B&H). The aim of this paper is to develop a new integrated Entropy-Fuzzy PIPRECIA (PIvot Pairwise RElative Criteria Importance Assessment)-DEA (Data Envelopment Analysis) model for determining the state of safety in B&H under particular conditions of uncertainty. Additionally, the aim is to combine the advantages of linear programming (DEA), an objective method (Entropy), and a subjective method (Fuzzy PIPRECIA). In this way, an integrated objective–subjective model is created that provides accurate and balanced decision-making through their integration. Eleven sustainable criteria were defined and divided into six inputs and five outputs. The Entropy model was used to determine the weight values of the inputs, while due to the nature of the outputs, Fuzzy PIPRECIA was used to evaluate them. After the application of the two methods, the way of averaging their values was defined. The DEA model, which implies an input- and output-oriented model, was applied to determine which railway sections have satisfactory performance in terms of safety. Two sections were eliminated from further computation due to extremely poor performance and high risk. Then, the weighted overall efficiency ranking method was applied to determine the final ranking of the railway sections. The results obtained were verified through a sensitivity analysis, which involved changing the impact of the five most significant criteria and a comparison with two Multi-Criteria Decision-Making (MCDM) methods.

M. Leiser, Edina Harbinja

e.harbinja@aston.ac.uk #online harms, duty of care, platform regulation, online safety This article critiques key proposals of the United Kingdom’s “Online Harms” White Paper; in particular, the proposal for new digital regulator and the imposition of a “duty of care” on platforms. While acknowledging that a duty of care, backed up by sanctions works well in some environments, we argue is not appropriate for policing the White Paper’s identified harms as it could result in the blocking of legal, subjectively harmful content. Furthermore, the proposed regulator lacks the necessary independence and could be subjected to political interference. We conclude that the imposition of a duty of care will result in an unacceptable chilling effect on free expression, resulting in a draconian regulatory environment for platforms, with users’ digital rights adversely affected. Content Not Available

D. Fajgenbaum, David Wu, A. Goodman, R. Wong, A. Chadburn, S. Nasta, G. Srkalović, S. Mukherjee et al.

Idiopathic multicentric Castleman disease (iMCD) is a rare immunologic disorder characterized by systemic inflammation, multicentric lymphadenopathy, and organ dysfunction. Enlarged lymph nodes demonstrate a spectrum of characteristic but variable histopathologic features historically categorized into hyaline vascular (HV) (or hypervascular [HyperV] more recently), plasmacytic, or “mixed.” Though the etiology is unknown, a pro‐inflammatory cytokine storm, often involving interleukin‐6 (IL‐6), contributes to pathogenesis. Anti‐IL‐6 therapy with siltuximab is the only FDA‐ or EMA‐approved treatment based on efficacy and safety in multiple studies. Importantly, no patients considered to have HV histopathology achieved the primary endpoint in the Phase II study. NCCN currently recommends siltuximab first‐line for iMCD, except for patients considered to have HV histopathology. We investigated whether histopathologic subtype should guide siltuximab treatment decisions. Secondary analyses of clinical trial and real‐world data revealed similar clinical benefit across histopathologic subtypes. Notably, only 18 of 79 patients in the Phase II study were consistently classified into histopathologic subtype by three independent review panels, demonstrating limited reliability to guide treatment decisions. Real‐world data further demonstrate siltuximab's effectiveness in patients considered to have HV (or HyperV). Though histopathology is a critical component for diagnosis, there is insufficient evidence to guide treatment based solely on lymph node histopathologic subtype.

M. Banožić, K. Aladić, I. Jerković, S. Jokić

BACKGROUND Volatile organic compounds are present at very low concentration, but exhibit important influence on flavor and aroma of tobacco leaves and products. During tobacco processing, at different stages, tobacco wastes are occurred. Since they are delivered directly from tobacco plant, they are expected to have similar aroma profile. RESULTS The volatile composition of 3 types of tobacco waste (scrap, dust and midrib) was characterized for the first time and compared with tobacco leaves volatile composition. Ultrasound-assisted extraction (UAE) with hexane followed by gas chromatography and mass spectrometry (GC-MS) was successfully applied. Different UAE parameters (temperature, time and solvent-solid ratio) showed significant influence on the volatile profiles of obtained extracts. The most important compounds in tobacco leaves, scrap and dust with the highest abundance were nicotine (up to 87.5%), 4,8,13-duvatriene-1,3-diol (up to 16.2%) and neophytadiene (up to 9.4%). In midrib only nicotine was present in all extracts. The most abundant compounds in the extracts were quantified and subjected to optimization, using response surface methodology (RSM). CONCLUSION Regression analysis showed that 83-98% of the variation was explained by the obtained models. The experimentally obtained values agreed with those predicted, thus indicating suitability of the model employed and the success of RSM in optimizing of the extraction conditions. This article is protected by copyright. All rights reserved.

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