8 research outputs found
Conversion of a wheel excavator to work on the railway superstructure
Práce pojednává o konstrukčním návrhu nakolejovacích adaptérů, které jsou součástí dvoucestného podvozku rypadla. Obsažena je pevnostní analýza pomocí výpočtu metodou konečných prvků a zhodnocení výsledků. Na základě výpočtů byl vytvořen návrh optimalizačních úprav konstrukce. Zahrnuto je i vyhodnocení souladu s legislativou pro provoz na železnici.Diploma thesis discusses a design of a rail equipment that provides a rail capapility to a classic excavator. Strenght calculation using FEM method and data evaluation is included in. A concept of structure alterations is provided as a result of calculation. Evaluation of compliance with measures of rail operation is also present.
Ethanol ablation of thyroid cysts in the young with a focus on efficacy and quality of life
Objective: Ultrasound-guided percutaneous ethanol injection therapy (US-PEIT) is used in patients with recurrent symptomatic thyroid cysts as a credible alternative to surgery. Young patients commonly do not wish to undergo surgery and prefer ethanol ablation, if available. The effect of this approach on quality of life is an essential factor in deciding on the treatment options, especially in the young with a long life expectancy and no comorbidity.
Methods: We performed US-PEIT in a cohort of young patients, 15–30 years, from 2015 to 2020. The patients’ general quality of life (QoL), self-reported compression symptoms and neck appearance were evaluated.
Results: The cohort comprised 59 patients with 63 cysts, more women than men, with a mean age of 23.8 years. About 1.5 mL of injected alcohol were needed to reach a 90.7% mean cyst volume reduction ratio in 12 months. The method did not fail in any of the patients; a single US-PEIT session was undertaken in 46% of them. The procedure significantly improved each of the patients’ symptoms with a significant total score difference (P < 0.001). The total symptom score correlated with the initial cyst volume (P = 0.002; r = 0.395). The mean QoL score by SF-36 6 months after the last US-PEIT was significantly different for physical component summary 56.5 (P < 0.001) but not different for mental component summary 47.7 (P = 0.125), compared to age-corresponding norms.
Conclusions: US-PEIT is a safe and effective method for the young, leading to improvements in cosmetic and subjective complaints, and should also be considered as first-line treatment in the young
The large area detector onboard the eXTP mission
The Large Area Detector (LAD) is the high-throughput, spectral-timing instrument onboard the eXTP mission, a flagship
mission of the Chinese Academy of Sciences and the China National Space Administration, with a large European
participation coordinated by Italy and Spain. The eXTP mission is currently performing its phase B study, with a target
launch at the end-2027. The eXTP scientific payload includes four instruments (SFA, PFA, LAD and WFM) offering
unprecedented simultaneous wide-band X-ray timing and polarimetry sensitivity. The LAD instrument is based on the
design originally proposed for the LOFT mission. It envisages a deployed 3.2 m2 effective area in the 2-30 keV energy
range, achieved through the technology of the large-area Silicon Drift Detectors - offering a spectral resolution of up to
200 eV FWHM at 6 keV - and of capillary plate collimators - limiting the field of view to about 1 degree. In this paper
we will provide an overview of the LAD instrument design, its current status of development and anticipated
performance
Global transpiration data from sap flow measurements : the SAPFLUXNET database
Plant transpiration links physiological responses of vegetation to water supply and demand with hydrological, energy, and carbon budgets at the land-atmosphere interface. However, despite being the main land evaporative flux at the global scale, transpiration and its response to environmental drivers are currently not well constrained by observations. Here we introduce the first global compilation of whole-plant transpiration data from sap flow measurements (SAPFLUXNET, https://sapfluxnet.creaf.cat/, last access: 8 June 2021). We harmonized and quality-controlled individual datasets supplied by contributors worldwide in a semi-automatic data workflow implemented in the R programming language. Datasets include sub-daily time series of sap flow and hydrometeorological drivers for one or more growing seasons, as well as metadata on the stand characteristics, plant attributes, and technical details of the measurements. SAPFLUXNET contains 202 globally distributed datasets with sap flow time series for 2714 plants, mostly trees, of 174 species. SAPFLUXNET has a broad bioclimatic coverage, with woodland/shrubland and temperate forest biomes especially well represented (80 % of the datasets). The measurements cover a wide variety of stand structural characteristics and plant sizes. The datasets encompass the period between 1995 and 2018, with 50 % of the datasets being at least 3 years long. Accompanying radiation and vapour pressure deficit data are available for most of the datasets, while on-site soil water content is available for 56 % of the datasets. Many datasets contain data for species that make up 90 % or more of the total stand basal area, allowing the estimation of stand transpiration in diverse ecological settings. SAPFLUXNET adds to existing plant trait datasets, ecosystem flux networks, and remote sensing products to help increase our understanding of plant water use, plant responses to drought, and ecohydrological processes. SAPFLUXNET version 0.1.5 is freely available from the Zenodo repository (https://doi.org/10.5281/zenodo.3971689; Poyatos et al., 2020a). The "sapfluxnetr" R package - designed to access, visualize, and process SAPFLUXNET data - is available from CRAN.Peer reviewe
Fyzikální modelování na malé obloukové peci
Prezenční410 - Katedra elektroenergetikyNeuveden
The large area detector onboard the eXTP mission
The Large Area Detector (LAD) is the high-throughput, spectral-timing instrument onboard the eXTP mission, a flagship mission of the Chinese Academy of Sciences and the China National Space Administration, with a large European participation coordinated by Italy and Spain. The eXTP mission is currently performing its phase B study, with a target launch at the end-2027. The eXTP scientific payload includes four instruments (SFA, PFA, LAD and WFM) offering unprecedented simultaneous wide-band X-ray timing and polarimetry sensitivity. The LAD instrument is based on the design originally proposed for the LOFT mission. It envisages a deployed 3.2 m2 effective area in the 2-30 keV energy range, achieved through the technology of the large-area Silicon Drift Detectors - offering a spectral resolution of up to 200 eV FWHM at 6 keV - and of capillary plate collimators - limiting the field of view to about 1 degree. In this paper we will provide an overview of the LAD instrument design, its current status of development and anticipated performance
The enhanced x-ray timing and polarimetry mission – eXTP: an update on its scientific cases, mission profile and development status
The enhanced x-ray timing and polarimetry mission (eXTP) is a flagship observatory for x-ray timing, spectroscopy and polarimetry developed by an international consortium. Thanks to its very large collecting area, good spectral resolution and unprecedented polarimetry capabilities, eXTP will explore the properties of matter and the propagation of light in the most extreme conditions found in the universe. eXTP will, in addition, be a powerful x-ray observatory. The mission will continuously monitor the x-ray sky, and will enable multi-wavelength and multi-messenger studies. The mission is currently in phase B, which will be completed in the middle of 2022
Global transpiration data from sap flow measurements: the SAPFLUXNET database
Plant transpiration links physiological responses of vegetation to water supply and demand with hydrological, energy, and carbon budgets at the land–atmosphere interface. However, despite being the main land evaporative flux at the global scale, transpiration and its response to environmental drivers are currently not well constrained by observations. Here we introduce the first global compilation of whole-plant transpiration data from sap flow measurements (SAPFLUXNET, https://sapfluxnet.creaf.cat/, last access: 8 June 2021). We harmonized and quality-controlled individual datasets supplied by contributors worldwide in a semi-automatic data workflow implemented in the R programming language. Datasets include sub-daily time series of sap flow and hydrometeorological drivers for one or more growing seasons, as well as metadata on the stand characteristics, plant attributes, and technical details of the measurements. SAPFLUXNET contains 202 globally distributed datasets with sap flow time series for 2714 plants, mostly trees, of 174 species. SAPFLUXNET has a broad bioclimatic coverage, with woodland/shrubland and temperate forest biomes especially well represented (80 % of the datasets). The measurements cover a wide variety of stand structural characteristics and plant sizes. The datasets encompass the period between 1995 and 2018, with 50 % of the datasets being at least 3 years long. Accompanying radiation and vapour pressure deficit data are available for most of the datasets, while on-site soil water content is available for 56 % of the datasets. Many datasets contain data for species that make up 90 % or more of the total stand basal area, allowing the estimation of stand transpiration in diverse ecological settings. SAPFLUXNET adds to existing plant trait datasets, ecosystem flux networks, and remote sensing products to help increase our understanding of plant water use, plant responses to drought, and ecohydrological processes. SAPFLUXNET version 0.1.5 is freely available from the Zenodo repository (https://doi.org/10.5281/zenodo.3971689; Poyatos et al., 2020a). The “sapfluxnetr” R package – designed to access, visualize, and process SAPFLUXNET data – is available from CRAN