Search results for " Nuclear"
showing 10 items of 11776 documents
Health Indicator for Low-Speed Axial Bearings Using Variational Autoencoders
2020
This paper proposes a method for calculating a health indicator (HI) for low-speed axial rolling element bearing (REB) health assessment by utilizing the latent representation obtained by variational inference using Variational Autoencoders (VAEs), trained on each speed reference in the dataset. Further, versatility is added by conditioning on the speed, extending the VAE to a conditional VAE (CVAE), thereby incorporating all speeds in a single model. Within the framework, the coefficients of autoregressive (AR) models are used as features. The dimensionality reduction inherent in the proposed method lowers the need of expert knowledge to design good condition indicators. Moreover, the sugg…
Surface Characteristics of Machined Polystyrene with 3D Printed Thermoplastic Tool
2020
An effort is made in this work to appraise the surface characteristics of machined expandable polystyrene (EPS) with a novel 3D printed thermoplastic acrylonitrile-butadiene-styrene (ABS) tool. Linear grooves on EPS were made on a vertical milling machine that was modified to conduct experiments in the laboratory. The tests were designed as per the Taguchi L9 based factorial design of experimentation while varying process parameters such as depth of cut, spindle speed, and feed rate. The machining responses dimensional accuracy and surface roughness of the machined grooves were studied. Furthermore, the surface topography of the machined specimens was considered to investigate the mechanism…
Experimental Research on the Cutting of Metal Materials by Electrical Discharge Machining with Contact Breaking with Metal Band as Transfer Object
2020
The scientific paper presents practical research carried out by a mixed team of Romanian researchers from universities and the business environment. The research consists in applying the process of cutting metallic materials through electrical discharge machining with contact breaking using a metal band as a transfer object. The research was implemented with the help of a specially designed installation in the laboratory and subsequently all the necessary steps were taken to obtain the patent for it. Various metallic materials were cut using this process, but first of all, high alloy steels. In the global research conducted by the authors, active experimental programs and classic experiment…
Abnormal Textures Identification Based on Digital Hilbert Optics Methods: Fundamental Transforms and Models
2017
The article presents the abnormal textures identification technology based on structural and statistical models of amplitude-phase images (APIm) – multidimensional data arrays (semantic models) and statistical correlation analysis methods using the generalized discrete Hilbert transforms (DHT) – 2D Hilbert (Foucault) isotropic (HTI), anisotropic (HTA) and total transforms – AP-analysis (APA) to calculate the APIm. The identified fragments of textures are obtained as examples of experimental observation of real mammograms contains areas of pathological tissues. The DHT based information technology as conceptual chart description is discussed and illustrated with DHO domain images. As additio…
DESDEO: The Modular and Open Source Framework for Interactive Multiobjective Optimization
2021
Interactive multiobjective optimization methods incorporate preferences from a human decision maker in the optimization process iteratively. This allows the decision maker to focus on a subset of solutions, learn about the underlying trade-offs among the conflicting objective functions in the problem and adjust preferences during the solution process. Incorporating preference information allows computing only solutions that are interesting to the decision maker, decreasing computation time significantly. Thus, interactive methods have many strengths making them viable for various applications. However, there is a lack of existing software frameworks to apply and experiment with interactive …
2019
Final disposal of spent nuclear fuel (SNF) from nuclear power plants (NPPs) is an ethical issue with implications within and across generations. We address this issue from the perspective of nuclear communities that host nuclear waste disposal sites. These are primarily the communities that face injustice due to the potential radiological risks. A resident survey (n = 454) was conducted in two Finnish nuclear communities, i.e. Eurajoki and Pyhajoki, that are being considered as alternative sites for a second repository for SNF. The nuclear waste management (NWM) company Posiva is already building a repository in Eurajoki, the first in Finland. These communities are in different stages of th…
Ecografía intestinal y abdomen agudo: más allá de la apendicitis aguda
2021
Resumen El abdomen agudo es un motivo de consulta habitual en los servicios de urgencias. Sus causas son multiples, y entre ellas se encuentran diversas enfermedades del tracto gastrointestinal. Si bien la tomografia computarizada es la tecnica mas aceptada, con frecuencia se lleva a cabo una ecografia abdominal inicialmente, mediante la cual es posible establecer la sospecha de patologia intestinal. Este articulo describe las caracteristicas ecograficas de diversos trastornos intestinales que cursan con abdomen agudo, como la diverticulitis aguda, la obstruccion intestinal, la perforacion gastrointestinal, la isquemia intestinal, la necrosis aguda de la grasa intraabdominal y una miscelane…
Paraganglioma carotídeo maligno. A propósito de un caso
2019
Resumen Los tumores del cuerpo carotideo son neoplasias poco frecuentes, de lento crecimiento, muy destructivos y vascularizados, que tienen un origen neuroectodermico. Los tumores malignos representan el 5-13% de los casos y presentan un comportamiento agresivo local con infiltracion de los ganglios linfaticos adyacentes o metastasis a distancia. Presentamos el caso de un varon de 60 anos al que en el estudio por dolor y parestesias en miembro superior se le realiza una resonancia magnetica donde se visualiza una gran tumoracion en el espacio carotideo izquierdo, la cual se biopsio obteniendo el diagnostico histologico de paraganglioma. Al realizar el estudio de extension se identifico la …
Direct flow separation strategy, to isolate no-carrier-added 90Nb from irradiated Mo or Zr targets
2016
Abstract 90Nb has an intermediate half-life of 14.6 h, a high positron branching of 53% and optimal β + emission energy of only E mean 0.35 MeV per decay. These favorable characteristics suggest it may be a potential candidate for application in immuno-PET. Our recent aim was to conduct studies on distribution coefficients for ZrIV and NbV in mixtures of HCl/H2O2 and HCl/oxalic acid for anion exchange resin (AG 1 × 8) and UTEVA resin to develop a “direct flow” separation strategy for 90Nb. The direct flow concept refers to a separation accomplished using a single eluent on multiple columns, effectively streamlining the separation process and increasing the time efficiency. Finally, we also …
Complexation des acides aminés basiques arginine, histidine et lysine avec l’ADN plasmidique en solution aqueuse : participation à la capture de radi…
2016
L’environnement chimique de l’ADN en situation biologique est complexe notam-ment en raison de la presence d’histones, proteines nucleaires, associees en quantite approximativement egales a l’ADN pour former la chromatine. Les histones possedent de nombreux radicaux basiques arginine et lysine charges positivement et dont la majorite se trouve sur les chaines emergentes, l’ADN presente quant a lui des charges negatives sur ses groupements phosphates localises tout au long de la double helice. Dans cette etude, la complexite de la structure de la chromatine nucleaire est dans un premier temps mimee en solution aqueuse par la formation de complexes entre un ADN plasmidique sonde et les trois …