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81.
The main aim of this experimental work is to find out possible improvement in thermal protective performance of firefighter protective clothing when subjected to different level of radiant heat flux density. Firefighter protective clothing normally consists of three layers: outer shell, moisture barrier and thermal liner. When thermal protective performance of firefighter protective clothing is enhanced, the time of exposure against radiant heat flux is increased, which will provide extra amount of time to firefighter to carry on their work without suffering from severe skin burn injuries. In this study, the exterior side of outer shell was coated with nano-silver metallic particle through magnetron sputtering technology. Coating of outer shell with nano-silver particles was performed at three level of thickness, i.e. 1, 2 and 3?µm, respectively. All the uncoated and silver coated specimens were then characterized on air permeability tester, Permetest and radiant heat transmission machine. It was observed that coating has insignificant difference on the air and water vapor permeability of specimen and a significant decline was recorded for the value of transmitted heat flux density Qc (kW/m2) and percentage transmission factor (%TF Qo) as compared to uncoated specimen when subjected to 10 kW/m2 and 20?kW/m2 indicating improvement of thermal protective performance. These values go on further reduction with increase in thickness of coating layer of nano-silver particles. 相似文献
82.
Kampf Thomas Sturm Volker J. F. Basse-Lüsebrink Thomas C. Fischer André Buschle Lukas R. Kurz Felix T. Schlemmer Heinz-Peter Ziener Christian H. Heiland Sabine Bendszus Martin Pham Mirko Stoll Guido Jakob Peter M. 《Magma (New York, N.Y.)》2019,32(1):63-77
Magnetic Resonance Materials in Physics, Biology and Medicine - In magnetic resonance imaging (MRI), compressed sensing (CS) enables the reconstruction of undersampled sparse data sets. Thus,... 相似文献
83.
Hernandez-Juarez Daniel Schneider Lukas Cebrian Pau Espinosa Antonio Vazquez David López Antonio M. Franke Uwe Pollefeys Marc Moure Juan C. 《International Journal of Computer Vision》2019,127(11-12):1643-1658
International Journal of Computer Vision - This work presents and evaluates a novel compact scene representation based on Stixels that infers geometric and semantic information. Our approach... 相似文献
84.
Marco Sarcletti Dustin Vivod Tobias Luchs Tobias Rejek Luis Portilla Lukas Müller Hanno Dietrich Andreas Hirsch Dirk Zahn Marcus Halik 《Advanced functional materials》2019,29(15)
Various hydrocarbons are efficiently extracted from water by using a new sorbent material based on covalently functionalized magnetic nanoparticles. The functionalization of the magnetite nanoparticles with a self‐assembled monolayer of hexadecylphosphonic acid renders the nanoparticles oleophilic and the magnetic nature of magnetite allows for simple extraction of the hydrocarbon‐soaked sorbent. The sorbent material is capable of extracting single contaminants such as alkanes and aromatics and complex hydrocarbon mixtures such as crude oils in high extraction rates of up to 14 times the sorbent volume. Experimental results are explained by molecular dynamics simulations on the adsorption of single components from a hydrocarbon‐water mixture to the alkylphosphonic acid layer on the nanoparticles. The core–shell sorbent material is highly stable and therefore, reusable over several successive extraction cycles without degradation. The extraction performance is determined at different water temperatures, different water sources, and different magnetic core materials and evaluated compared to heptadecanoic acid functionalized magnetite. The new sorbent material provides the opportunity for an efficient, reliable, inexpensive, and environmental friendly removal of hydrocarbons from water. 相似文献
85.
Romy Müller Laura Ullrich Ann‐Kathrin Dessel Amelie Bengsch Sebastian Heinze Tobias Müller Lukas Oehm 《人机工程学与制造业中的人性因素》2019,29(1):44-62
In the processing industry, frequent faults call for assistance in diagnosis, and case‐based reasoning (CBR) can provide solutions applied by other operators in the past. This study investigated whether salient case ratings promote an uncritical acceptance of solutions. In 2 experiments, subjects diagnosed faults with a simulated CBR system, and ratings were presented in graphical or verbal format. In most trials, the case with the highest rating provided the correct solution, while in catch‐trials, it did not. Graphical ratings were hypothesized to speed up solutions but discourage cross‐checking and lead to errors in catch‐trials. These hypotheses were not confirmed, even though Experiment 2 maximized the incentive of relying on case ratings. While graphical ratings led subjects to start with the most highly rated case, they did not impair situation analysis and accuracy. The results suggest that during fault diagnosis people are not easily misled into overtrusting a CBR system. 相似文献
86.
Lukas Mathur Martine Ballinger Ramesh Utharala Christoph A. Merten 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(9)
Tailoring patient‐specific treatments for cancer is necessary in order to achieve optimal results but requires new diagnostic approaches at affordable prices. Microfluidics has immense potential to provide solutions for this, as it enables the processing of samples that are not available in large quantities (e.g., cells from patient biopsies), is cost efficient, provides a high level of automation, and allows the set‐up of complex models for cancer studies. In this review, individual solutions in the fields of genetics, circulating tumor cell monitoring, biomarker analysis, phenotypic drug sensitivity tests, and systems providing controlled environments for disease modeling are discussed. An overview on how these early stage achievements can be combined or developed further is showcased, and the required translational steps before microfluidics becomes a routine tool for clinical applications are critically discussed. 相似文献
87.
Scientometrics - This paper builds on previous work by reviewing the key literature relating to the rise in co-authorship in economics and by presenting further new evidence on several features of... 相似文献
88.
89.
Lukas Strizik Vit Prokop Jan Hrabovsky Tomas Wagner Takeshi Aoki 《Journal of Materials Science: Materials in Electronics》2017,28(10):7053-7063
The article presents the formulas of quadrature frequency resolved spectroscopy (QFRS) on the upconversion photoluminescence (UCPL) of rare-earth (RE) doped materials on the general M-level model. The formulas are derived in matrix-equation form with the first-order perturbation on the rate equations at the M energy-levels of RE ion. The QFRS spectra for three different UCPL processes, i.e., the excited state absorption (ESA), energy transfer upconversion (ETU) and photon avalanche (PA) via cross relaxation process (CRP) in a particular case of M?=?3 are demonstrated with the respective salient features of the excitation power dependence. We have measured the QFRS on the UCPL (4 S 3/2 → 4 I 15/2) by systematically varying Er-doping in Ge28.1Ga6.3S65.6 chalcogenide glass from 0.01 to 0.5 at.% as well as 975 nm excitation power. Thereby the relaxation rates k 1 at the intermediate level 4 I 11/2, k 2 at the top level 4 S 3/2 and ETU parameter w are determined as a function of Er concentration. The UCPL dynamics on the basis of the formulas for the 3-level model is interpreted in terms of the determined parameters. 相似文献
90.
Wieczorek Oliver Unger Saïd Riebling Jan Erhard Lukas Koß Christian Heiberger Raphael 《Scientometrics》2021,126(12):9699-9731
Scientometrics - We map the topic structure of psychology utilizing a sample of over 500,000 abstracts of research articles and conference proceedings spanning two decades (1995–2015). To do... 相似文献