Search results for "FN"

EU-TIRADS salīdzinājums ar Latvijā izmantoto modificēto TIRAD sistēmu vairogdziedzera mezglu malignitātes riska novērtēšanai

2019

TIRADS ir vairogdziedzera mezglu malignitātes riska novērtēšanas sistēma, kuras galvenie mērķi ir atvieglot endokrinologu un radiologu – diagnostu darbu, palīdzot atlasīt pacientus tālākai vairogdziedzera mezglu punkcijas biopsijas veikšanai, kas mūsdienās ir objektīvākā metode varogdziedzera mezglu malignitātes apstiprināšanai. Pastāv vairāki TIRADS modeļi, no kurām Latvijā tika izmantota 2011.gada modificēta sistēma. Pētījuma mērķis bija noskaidrot un salīdzināt galvenās atšķirības starp vairogdziedzera US klašu interpretāciju, kā arī malignitātes riska atšķirības Eiropā un Latvijā izmantotajās TIRAD sistēmās. Petījuma gaitā tika izvirzīta hipotēze, ka vairogdziedzera mezgliem, kuri lokal…

Los espacios públicos de la cotidianeidad / 2

2006

Compensation of compliance errors in parallel manipulators composed of non-perfect kinematic chains

2012

The paper is devoted to the compliance errors compensation for parallel manipulators under external loading. Proposed approach is based on the non-linear stiffness modeling and reduces to a proper adjusting of a target trajectory. In contrast to previous works, in addition to compliance errors caused by machining forces, the problem of assembling errors caused by inaccuracy in the kinematic chains is considered. The advantages and practical significance of the proposed approach are illustrated by examples that deal with groove milling with Orthoglide manipulator.

Compliance error compensation technique for parallel robots composed of non-perfect serial chains

2012

The paper presents the compliance errors compensation technique for over-constrained parallel manipulators under external and internal loadings. This technique is based on the non-linear stiffness modeling which is able to take into account the influence of non-perfect geometry of serial chains caused by manufacturing errors. Within the developed technique, the deviation compensation reduces to an adjustment of a target trajectory that is modified in the off-line mode. The advantages and practical significance of the proposed technique are illustrated by an example that deals with groove milling by the Orthoglide manipulator that considers different locations of the workpiece. It is also de…

Fast MATLAB assembly of FEM matrices in 2D and 3D: Edge elements

2014

We propose an effective and flexible way to assemble finite element stiffness and mass matrices in MATLAB. We apply this for problems discretized by edge finite elements. Typical edge finite elements are Raviart-Thomas elements used in discretizations of H(div) spaces and Nedelec elements in discretizations of H(curl) spaces. We explain vectorization ideas and comment on a freely available MATLAB code which is fast and scalable with respect to time.

Mafic and ultra-mafic enclaves from Ustica island lava: inferences on deep magmatic processes

2005

Ustica Island, southern Tyrrhenian Sea, is constituted of Quaternary alkaline volcanics. Avariety of enclaves representative of deep to supra-crustal settings were recently found in a hawaiitic lava flow. Enclaves consist of: (i) Ultramafic meta-cumulates, i.e. clinopyroxenites and wherlites characterized by variably deformed porphyroclastic to granoblastic textures. (ii) Mafic cumulates, i.e. gabbros (F amphibole) and troctolites, the first often characterized by frequent amphibole breakdown coronas (olivine+Tiaugite+ plagioclase+magnetite+ilmenite+rhfnite) in response to an H2O decrease during the ascent, while the troctolites interpreted as meta-cumulates. (iii) Microsyenites, consist of…

Local structural investigation of hafnia-zirconia polymorphs in powders and thin films by X-ray absorption spectroscopy

2019

Björn Matthey (Fraunhofer IKTS, Dresden) is acknowledged for providing HfO2 and ZrO2 powders on short notice after DESY’s renowned customs office punished us. Parts of this research were carried out at Petra III at DESY, a member of the Helmholtz Association (HGF). The experiments on single Si:HfO2 thin film samples were performed at the CLAESS beamline at ALBA Synchrotron with the collaboration of ALBA staff. We would like to thank Edmund Welter for assistance (in using beamline P65) and DESY for enabling this research for proposal no. 20160591 and for travel support. T.S. acknowledges the German Research Foundation (DFG) for funding this work in the frame of the project “Inferox” (project…

Mechanical testing and numerical modelling of pull-wound carbon-epoxy spinnaker poles

2002

The paper deals with experimental testing and numerical simulation of the mechanical behaviour of multi-layer cylindrical coupons, of two different diameters, made in carbon-epoxy composite. The aim of the study is to provide a simple and effective numerical model that can be used as a design tool for structural elements having analogous geometrical and manufacturing characteristics. The numerical analysis, performed in the elastic regime with a standard finite element (FE) code, was strongly correlated with the laboratory determination of fibre-volume fractions and of some elastic parameters of the material system. Other parameters, like the shear modulus values G, were in fact appropriate…

PERCUTANEOUS US (ULTRA SOUND) GUIDED FINE NEEDLE ASPIRATION (FNA) OF ENDOTHORACIC NEOPLASM

2022

Introduction: Ultrasound (US)-guided fine needle aspiration (FNA) of percutaneous, transparietal endothoracic lesions, is a useful method in the diagnostic process for anatomopathological characterization. This sampling is a minimally invasive procedure, with a low complication rate and can be performed under loco-regional anesthesia Material and methods: We retrospectively studied (2009 to 2019) the utility of US guided transthoracic FNA in the diagnosis of suspected endothoracic lesions on 54 patients (34 men and 20 women), aged between 44 and 79 years, with pleural, pulmonary or mediastinal neoplasm viewable with an US examination. Results: The definitive diagnosis of malignant or benign…

Design of RC joints equipped with hybrid trussed beams and friction dampers

2021

Abstract The challenge of this research consists in the first attempt to apply a dissipative friction connection to beam-to-column joints with semi-prefabricated Hybrid Steel-Trussed Concrete Beams (HSTCB) and RC pillars cast in-situ. Nowadays, HSTCBs are widely adopted in civil and industrial buildings and, therefore, it is required to evaluate their compliance with the capacity design criteria and their seismic energy dissipation capability. However, the design of the reinforcement of such beams usually lead to the adoption of large amount of steel within the panel zone which becomes potentially vulnerable to the effects of seismic cyclic actions and dramatically reduce the dissipation ca…