119 research outputs found
FDG-PET positive pilomatrixoma — reconsidering multicentricity in Langerhans cell histiocytosis
We report a case of a woman who underwent a curative resection of an upper jaw tumor histologically verified as eosinophilic granuloma. To exclude possible multiorgan involvement, PET/CT imaging was performed and revealed a metabolically active, partially calcified lesion located on the chest wall surface and clinically corresponding to a gradually developing, round, subcutaneous infiltrate with erythematous overlying skin. After complete extirpation, the pathological finding was consistent with pilomatrixoma surprisingly, thus dismissing the suspected diagnosis of multi-system Langerhans cell histiocytosis
Određivanje pomaka opterećenoga drvenog stolca primjenom korelacije digitalne slike
The subject of the research is a ready to assemble (RTA) chair constructed of plywood by a CNC machine. The standard test of seat and back of the chair according to the Czech Standard CSN EU 1728 was supplemented with an optical method of digital image correlation (DIC). The aim of the research was to discover mechanical principles of the construction and to develop a methodology of standardized furniture testing. Results of experimental measurement show the response of the chair construction in a form of displacement fields, strain fields, charts and vectors depicting displacement of the observed points. The results can be used to improve mechanical properties of the construction, as well as to develop a shape of the product or specific parts of the product. Besides furniture testing laboratories and research institutes, engineers from development departments of furniture making companies or industrial designers can easily use the presented method.Predmet istraživanja bio je stolac spreman na sklapanje (RTA), izrađen od uslojenog drva na CNC stroju. Standardni test sjedala i naslona stolca prema češkom standardu CSN EU 1728 dopunjen je optičkom metodom korelacije digitalne slike (DIC). Cilj istraživanja bio je otkriti mehanička načela konstrukcije te obogatiti metodologiju standardiziranog ispitivanja namještaja. Rezultati eksperimentalnih mjerenja prikazuju reakciju konstrukcije stolca u obliku polja pomaka, polja naprezanja te grafikona i vektora koji predočuju pomake promatranih točaka. Rezultati se mogu iskoristiti za poboljšanje mehaničkih svojstava konstrukcije, kao i za razvoj oblika proizvoda ili ispitivanih dijelova. Osim u laboratoriju za ispitivanje namještaja ili u istraživačkim institutima, prikazanom se metodom lako mogu koristiti inženjeri razvojnih odjela u tvrtkama za proizvodnju namještaja li industrijski dizajneri
Calibration of RGB camera with velodyne LiDAR
Calibration of the LiDAR sensor with RGB camera finds its usage in many application fields from enhancing
image classification to the environment perception and mapping. This paper presents a pipeline for mutual pose
and orientation estimation of the mentioned sensors using a coarse to fine approach. Previously published methods
use multiple views of a known chessboard marker for computing the calibration parameters, or they are limited to
the calibration of the sensors with a small mutual displacement only. Our approach presents a novel 3D marker for
coarse calibration which can be robustly detected in both the camera image and the LiDAR scan. It also requires
only a single pair of camera-LiDAR frames for estimating large sensors displacement. Consequent refinement step
searches for more accurate calibration in small subspace of calibration parameters. The paper also presents a novel
way for evaluation of the calibration precision using projection error
Carsharing and further forms of shared mobility: case study from Pilsen
Tento příspěvek byl podpořen z projektu SGS-2021-022 "Výzkum kvantitativních metod v aplikaci na
vybrané ekonomické problémy" Fakulty ekonomické Západočeské univerzity v Plzni.The sharing economy is a phenomenon of the present time. The principle of sharing is successfully
used in the field of mobility in the form of services such as bikesharing, carsharing or ridesharing. This paper
focuses on the analysis of the offer of shared mobility services in the fourth largest city of the Czech Republic,
Pilsen. Potential users can choose from three carsharing possibilities in Pilsen, as well as bicycle sharing
service. Scooter sharing service (launched previously) is unavailable in 2022. The situation in the field of
shared mobility in Pilsen is specific as, in addition to the offer of private companies, carsharing is also operated
by a city-owned company (operating public transport). Further, based on the conducted original research, the
awareness of a specific carsharing service among the city residents (public transport users) is mapped. The
results show that although awareness of the service is relatively high (more than 70% of respondents), the
number of actual users is relatively low. It was also found that women have significantly lower service
experience and awareness of carsharing compared to men. Advertising on social media and in public
transport vehicles can be assessed as the most effective media in communicating the carsharing offer to the
examined segment
Secondary hardening of low-alloyed creep-resistant steel welds
The T24 steel represents the new generation of low-alloyed creep resistant steels with higher creep resistance and
lower carbon content. It was designed as prospective material for membrane waterwalls of ultra super critical (USC)
power plants, enabling to avoid preheating and post weld heat treatment (PWHT) during welding. However, our
investigations concerning secondary hardening of vanadium containing low-alloyed steels show that non-tempered
welded joints undergo a signifi cant increase in hardness during exposure to operating temperature. The results
then imply that PWHT of T24 steel welds is necessary and this idea is at present supported by the occurrence of
several troubles with new installations of USC blocks in Europe.Web of Science531282
Design and Simulation of High Performance Parallel Architectures Using the ISAC Language
Most of modern embedded systems for multimediaand network applications are based on parallel data streamprocessing. The data processing can be done using very longinstruction word processors (VLIW), or using more than onehigh performance application-specific instruction set processor(ASIPs), or even by their combination on single chip.Design and testing of these complex systems is time-consumingand iterative process. Architecture description languages (ADLs)are one of the most effective solutions for single processor design.However, support for description of parallel architectures andmulti-processor systems is very low or completely missing innowadays ADLs. This article presents utilization of newextensions for existing architecture description language ISAC.These extensions are used for easy and fast prototyping andtesting of parallel based systems and processors
An investigation of thermoelectric generators used as energy harvesters in a water consumption meter application
In this study, we present the results of measuring the performance of selected Peltier cells such as thermoelectric Peltier cooler modules (TEC), thermoelectric micro-Peltier cooler modules (TES), and thermoelectric Seebeck generator modules (TEG). The achieved results are presented in the form of graphs of powering system output voltage or power efficiency functions of the load impedance. Moreover, a technical solution is also presented that consists of designing a water consumption power supply system, using a renewable energy source in the form of a Peltier cell. The developed measuring system does not require additional batteries or an external power source. The energy needed to power the system was obtained from the temperature difference between two sides of a thermoelectric cell, caused by the measured medium which was flowing in a copper water pipe. All achieved results were investigated for the temperature difference from 1 to 10 K in relation to the ambient temperature.Web of Science1413art. no. 376
Assessment of the influence of shortening the duration of TRT (thermal response test) on the precision of measured values
In this paper the results of testing thermal parameters of the rock environment and measurement of borehole temperature profiles of the newly constructed experimental underground heat storage (BTES (Borehole Thermal Energy Storage)) in Paskov (Czech Republic) obtained with the TRT (thermal response method) and temperature measurement on boreholes at selected depth levels are summarised. The TRT measurement series on eight boreholes has shown the possibility to compare the differences among individual measurements in a practically identical rock environment. The temperature profiling of boreholes enabled studying the dynamics of temperature changes occurring in the rock environment as a reaction to the heat supply during the TRT.
The measurement series was performed with the aim to assess the possibility of shortening the TRT duration while maintaining the acceptable precision of the measured results. For this reason the software simulation of shortening the TRT duration to 24 h was performed, and the influence of such shortening to the precision of determination of values λλ and RBRB was studied. The simulation has shown that shortening the test to 24 h in our case would have brought an acceptable amount of inaccuracy with regard to the dispersion of measured values obtained from the real test.Web of Science6412912
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