Silica final lenses under HiPER laser fusion reactor operation conditions

We have studied the thermo-mechanical response and atomistic degradation of final lenses in HiPER project. Final silica lenses are squares of 75 × 75 cm2 with a thickness of 5 cm. There are two scenarios where lenses are located at 8 m from the centre: •HiPER 4a, bunches of 100 shots (maximum 5 DT shots <48 MJ at ≈0.1 Hz). No blanket in chamber geometry. •HiPER 4b, continuous mode with shots ≈50 MJ at 10 Hz to generate 0.5 GW. Liquid metal blanket in chamber design

An overview on armor research for the laser fusion project HiPER

During the current preparatory phase of the European laser fusion project HiPER, an intensive effort has being placed to identify an armour material able to protect the internal walls of the chamber against the high thermal loads and high fluxes of x-rays and ions produced during the fusion explosions. This poster addresses the different threats and limitations of a poly-crystalline Tungsten armour. The analysis is carried out under the conditions of an experimental chamber hypothetically constructed to demonstrate laser fusion in a repetitive mode, subjected to a few thousand 48MJ shock ignition shots during its entire lifetime. If compared to the literature, an extrapolation of the thermomechanical and atomistic effects obtained from the simulations of the experimental chamber to the conditions of a Demo reactor (working 24/7 at hundreds of MW) or a future power plant (producing GW) suggests that “standard” tungsten will not be a suitable armour. Thus, new materials based on nano-structured W and C are being investigated as possible candidates. The research programme launched by the HiPER material team is introduced

Analytical Models of the Performance of IEEE 802.11p Vehicle to Vehicle Communications

The critical nature of vehicular communications requires their extensive testing and evaluation. Analytical models can represent an attractive and cost-effective approach for such evaluation if they can adequately model all underlying effects that impact the performance of vehicular communications. Several analytical models have been proposed to date to model vehicular communications based on the IEEE 802.11p (or DSRC) standard. However, existing models normally model in detail the MAC (Medium Access Control), and generally simplify the propagation and interference effects. This reduces their value as an alternative to evaluate the performance of vehicular communications. This paper addresses this gap, and presents new analytical models that accurately model the performance of vehicle-to-vehicle communications based on the IEEE 802.11p standard. The models jointly account for a detailed modeling of the propagation and interference effects, as well as the impact of the hidden terminal problem. The model quantifies the PDR (Packet Delivery Ratio) as a function of the distance between transmitter and receiver. The paper also presents new analytical models to quantify the probability of the four different types of packet errors in IEEE 802.11p. In addition, the paper presents the first analytical model capable to accurately estimate the Channel Busy Ratio (CBR) metric even under high channel load levels. All the analytical models are validated by means of simulation for a wide range of parameters, including traffic densities, packet transmission frequencies, transmission power levels, data rates and packet sizes. An implementation of the models is provided openly to facilitate their use by the community

Industrial Applications of Laser Neutron Source

The industrial applications of the intense neutron source have been widely explored because of the unique features of the neutron-matter interaction. Usually, intense neutron sources are assembled with fission reactors or high energy ion accelerators. The big size and high cost of these systems are the bottle neck to promote the industrial applications of intense neutrons. In this paper, we propose the compact laser driven neutron source for the industrial application. As the first step of our project for the versatile applications of laser driven neutron source, Li-neutron and/or Li-proton interactions have been investigated for the application to the development of Li battery

Efficacy of a Deep Learning Convolutional Neural Network System for Melanoma Diagnosis in a Hospital Population

The purpose of this study was to evaluate the efficacy in terms of sensitivity, specificity, and accuracy of the quantusSKIN system, a new clinical tool based on deep learning, to distinguish between benign skin lesions and melanoma in a hospital population. (2) Methods: A retrospective study was performed using 232 dermoscopic images from the clinical database of the Ramón y Cajal University Hospital (Madrid, Spain). The skin lesions images, previously diagnosed as nevus (n = 177) or melanoma (n = 55), were analyzed by the quantusSKIN system, which offers a probabilistic percentage (diagnostic threshold) for melanoma diagnosis. The optimum diagnostic threshold, sensitivity, specificity, and accuracy of the quantusSKIN system to diagnose melanoma were quantified. (3) Results: The mean diagnostic threshold was statistically lower (p < 0.001) in the nevus group (27.12 ± 35.44%) compared with the melanoma group (72.50 ± 34.03%). The area under the ROC curve was 0.813. For a diagnostic threshold of 67.33%, a sensitivity of 0.691, a specificity of 0.802, and an accuracy of 0.776 were obtained. (4) Conclusions: The quantusSKIN system is proposed as a useful screening tool for melanoma detection to be incorporated in primary health care systems.Depto. de Optometría y VisiónFac. de Óptica y OptometríaTRUEpu

The neighbor-locating-chromatic number of pseudotrees

Ak-coloringof a graphGis a partition of the vertices ofGintokindependent sets,which are calledcolors. Ak-coloring isneighbor-locatingif any two vertices belongingto the same color can be distinguished from each other by the colors of their respectiveneighbors. Theneighbor-locating chromatic number¿NL(G) is the minimum cardinalityof a neighbor-locating coloring ofG.In this paper, we determine the neighbor-locating chromatic number of paths, cycles,fans and wheels. Moreover, a procedure to construct a neighbor-locating coloring ofminimum cardinality for these families of graphs is given. We also obtain tight upperbounds on the order of trees and unicyclic graphs in terms of the neighbor-locatingchromatic number. Further partial results for trees are also established.Preprin

The Role of the Spatial and Temporal Radiation Deposition in Inertial Fusion Chambers: The case of HiPER

The first wall armour for the reactor chamber of HiPER will have to face short energy pulses of 5 to 20 MJ mostly in the form of x-rays and charged particles at a repetition rate of 5–10 Hz. Armour material and chamber dimensions have to be chosen to avoid/minimize damage to the chamber, ensuring the proper functioning of the facility during its planned lifetime. The maximum energy fluence that the armour can withstand without risk of failure, is determined by temporal and spatial deposition of the radiation energy inside the material. In this paper, simulations on the thermal effect of the radiation–armour interaction are carried out with an increasing definition of the temporal and spatial deposition of energy to prove their influence on the final results. These calculations will lead us to present the first values of the thermo-mechanical behaviour of the tungsten armour designed for the HiPER project under a shock ignition target of 48 MJ. The results will show that only the crossing of the plasticity limit in the first few micrometres might be a threat after thousands of shots for the survivability of the armour

TechnoFusion: new Spanish singular scientific-technical facility for fusion research

Technofusion is the scientific&technical installation for fusion research in Spain, based on three pillars: • It is an open facility to European users. • It is a facility with instrumentation not accesible to small research groups. • It is designed to be closely coordiated with the European Fusion Program. With a budget of 80-100 M€ over five years, several top laboratories will be constructe

Velocidad media de infiltración en un vertisol bajo distintos sistemas de labranza

Soil compaction is regarded as the most serious environmental problem caused by conventional agriculture. Few studies are concerned with the assessment of soil compaction using infiltration speed, specifically in the Vertisol soil characteristic of the main maize producing area of the Toluca-Atlacomulco Valley in central Mexico. The aim of this research was to examine the effect on infiltration speed and penetration resistance of a Vertisol soil when compacted by wheeled agricultural traffic in three different types of tillage systems: zero, minimal and conventional. Penetration resistance was measured on the wheel track with a portable digital penetrometer, and the mean infiltration speed was determined according to the double cylinder infiltrometer method. The pressure exerted by the number of wheeled traffic passes increased Vertisol soil compaction at 30 cm depth. Even though the benefits of zero tillage were similar to those showed by mínimum tillage during the experimental period, minimum tillage reported the highest infiltration spee

On the weak lensing masses of a new sample of galaxy groups

Galaxy group masses are important to relate these systems with the dark matter halo hosts. However, deriving accurate mass estimates is particularly challenging for low-mass galaxy groups. Moreover, calibration of observational mass-proxies using weak-lensing estimates have been mainly focused on massive clusters. We present here a study of halo masses for a sample of galaxy groups identified according to a spectroscopic catalogue, spanning a wide mass range. The main motivation of our analysis is to assess mass estimates provided by the galaxy group catalogue derived through an abundance matching luminosity technique. We derive total halo mass estimates according to a stacking weak-lensing analysis. Our study allows to test the accuracy of mass estimates based on this technique as a proxy for the halo masses of large group samples. Lensing profiles are computed combining the groups in different bins of abundance matching mass, richness, and redshift. Fitted lensing masses correlate with the masses obtained from abundance matching. However, when considering groups in the low-and intermediate-mass ranges, masses computed according to the characteristic group luminosity tend to predict higher values than the determined by the weak-lensing analysis. The agreement improves for the low-mass range if the groups selected have a central early-Type galaxy. Presented results validate the use of mass estimates based on abundance matching techniques, which provide good proxies to the halo host mass in a wide mass range.Fil: Gonzalez, Elizabeth Johana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Rodriguez, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Merchan, Manuel Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Garcia Lambas, Diego Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Makler, Martín. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro Internacional de Estudios Avanzados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Físicas. - Universidad Nacional de San Martín. Instituto de Ciencias Físicas; Argentina. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Chalela, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Pereira, Maria E. S.. University of Michigan. Department of Physics; Estados UnidosFil: Moraes, Bruno. Universidade Federal do Rio de Janeiro; BrasilFil: Shan, HuanYuan. Chinese Academy of Sciences; República de China. Shanghai Astronomical Observatory; Chin