3x3 Multibeam Network for a Triangular Array of Three Radiating Elements

A multibeam antenna study based on Butler network will be undertaken in this document. These antenna designs combines phase shift systems with multibeam networks to optimize multiple channel systems. The system will work at 1.7 GHz with circular polarization. Specifically, result simulations and measurements of 3 element triangular subarray will be shown. A 45 element triangular array will be formed by the subarrays. Using triangular subarrays, side lobes and crossing points are reduced

The H=xp model revisited and the Riemann zeros

Berry and Keating conjectured that the classical Hamiltonian H = xp is related to the Riemann zeros. A regularization of this model yields semiclassical energies that behave, in average, as the non trivial zeros of the Riemann zeta function. However, the classical trajectories are not closed, rendering the model incomplete. In this paper, we show that the Hamiltonian H = x (p + l_p^2/p) contains closed periodic orbits, and that its spectrum coincides with the average Riemann zeros. This result is generalized to Dirichlet L-functions using different self-adjoint extensions of H. We discuss the relation of our work to Polya's fake zeta function and suggest an experimental realization in terms of the Landau model.Comment: 5 pages, 3 figure

Factors associated with overeducation among recent graduates during labour market integration: The case of Catalonia (Spain)

Overeducation has usually been considered a phenomenon brought about during integration into the labour market. There is no single explanation, but rather several factors that are associated with overeducation. We analyse overeducation among graduates in Catalonia four years after finishing their degrees. The analysis is based on the self-assessment made by workers in surveys conducted by AQU (Catalan University Quality Assurance Agency) between 2008 and 2014 and we use logit and probit statistical models to determine the probability of a graduate being overeducated, depending on a wide range of economic, sociological, technological and academic variables. We use the Heckman methodology in the analysis. This study corroborates the results of previous studies on the relationship between wages, job satisfaction and overeducation. In addition, the results show, firstly, differences in levels of overeducation between different fields of study, most notably between 'Humanities and Arts' and 'Health Sciences'. Secondly, the results reveal the impact of the economic cycle on overeducation. Thirdly, the variables used in the statistical model exhibit stable behaviour and, as a result, they provide an explanation for overeducation as a structural phenomenon, regardless of the economic situation. Furthermore, other variables show a significant relationship with signalling theory and career mobility theory, which both explain the overeducation phenomenon. We especially emphasise the role of professional career development during undergraduate studies. Additionally, we found that the family socio-economic environment is relevant in explaining overeducation and, lastly, technological factors and aspects of the graduates' work environment also contribute to explaining the phenomenon

Autonomous vehicle control in CARLA Challenge

Congreso Campus FIT 2020. 24-26 junio 2020, onlineThe introduction of Autonomous Vehicles (AVs) in a realistic urban environment is an ambitious objective. AV validation on real scenarios involving actual objects such as cars or pedestrians in a wide range of traffic cases would escalate the cost and could generate hazardous situations. Consequently, autonomous driving simulators are quickly evolving to cover the gap to achieve a fully autonomous driving architecture validation. Most used 3D simulators in self-driving cars field are V-REP (Rohmer, E., 2013) and Gazebo (KOENIG, N. and HOWARD, A., 2004), due to an easy integration with ROS (QUIGLEY, 2009) platform to increase the interoperability with other systems. Those simulators provide accurate motion information (more appropriate for easier scenes like robotic arms) but not a realistic appearance and not allowing real-time systems, not being able to recreate complex traffic scenes. CARLA (DOSOVITSKIY, A., 2017) open-source AV simulator is designed to be able to train and validate control and perception algorithms in complex traffic scenarios with hyper-realistic environments. CARLA simulator allows to easily modify on-board sensors such as cameras or LiDAR, weather conditions and also the traffic scene to perform specific traffic cases. In Summer 2019, CARLA launched its driving challenge to allow everyone to test their own control techniques under the same traffic scenarios, scoring its performance regarding traffic rules. In this paper, the Robesafe researching group approach will be explained, detailing vehicle motion control and object detection adapted from Smart Elderly Car (GÓMEZ-HUÉLAMO, C., 2019) that lead the group to reach the 4th place in Track 3 challenge, where HD Map, Waypoints and environmental sensors data (LiDAR, RGB cameras and GPS) were provided.Ministerio de Ciencia, Innovación y UniversidadesComunidad de Madri

Nuevo índice para evaluar anomalías de elementos traza en suelos: el caso del SE español

In this work, an index is established to detect anomalies in trace elements in the soil. This index, which relates the total concentration of each element with the regional geochemical background value of the element considered, was defined by studying the levels of trace elements from different soils located in SE Spain. In the area, a previous screening of trace elements detected seven zones with anomalies and revealed two conflictive areas: Sierra Gador and Cabo de Gata. In each zone, a second sampling was undertaken at two different depths (0-20 cm and 20-40 cm). The results indicate that the main anomalies were due to arsenic (As), lead (Pb), and zinc (Zn). In Sierra Gador Pb was the element that registered the highest rate of enrichment with respect to the regional geochemical background, reaching values up to 270-fold higher in some samples. In this zone, more than 50% of the samples were anomalous in any of the trace elements studied (higher than regional geochemical background). In Cabo de Gata, As concentration was higher than the geochemical background in more than 40% of the samples; meanwhile Pb concentration was higher in 50% of the samples.En este trabajo establecemos un índice para detectar anomalías en el contenido de elementos traza en suelos. Este índice relaciona el contenido total de cada elemento traza con el fondo geoquímico regional, definido mediante el estudio de los niveles de elementos traza en diferentes suelos localizados en el sureste español. En un primer estudio sobre niveles de elementos traza en suelos del área de estudio detectaron siete zonas con anomalías, de las cuales dos fueron consideradas conflictivas: Sierra de Gádor y Cabo de Gata. En cada una de estas dos zonas se realizó un segundo estudio más exhaustivo a dos niveles de profundidad (0-20 y 20-40 cm). Los resultados indican que las principales anomalías correspondes a los niveles de As, Pb y Zn. En Sierra de Gádor el Pb es el elemento que presenta una mayor tasa de enriquecimiento con respecto al fondo geoquímico regional, con valores puntuales que lo superan hasta 270 veces. También en esta zona más del 50% de las muestras presentan anomalías en alguno de los elementos analizados. En Cabo de Gata el As supera el fondo geoquímico regional en más del 40% de las muestras; mientras que el Pb lo supera en el 50% de las muestras.This study has been made possible by the research Project no. 1550 of the Regional Environmental Department of the Andalusian Government

Aspergillus sydowii and other potential fungal pathogens in Gorgonian Octocorals of the Ecuadorian Pacific

Emerging fungal diseases are threatening ecosystems and have increased in recent decades. In corals, the prevalence and consequences of these infections have also increased in frequency and severity. Coral reefs are affected by an emerging fungal disease named aspergillosis, caused by Aspergillus sydowii. This disease and its pathogen have been reported along the Caribbean and Pacific coasts of Colombia. Despite this, an important number of coral reefs worldwide have not been investigated for the presence of this pathogen. In this work, we carried out the surveillance of the main coral reef of the Ecuadorian Pacific with a focus on the two most abundant and cosmopolitan species of this ecosystem, Leptogorgia sp. and Leptogorgia obscura. We collected 59 isolates and obtained the corresponding sequences of the Internal Transcribed Spacers (ITS) of the ribosomal DNA. These were phylogenetically analyzed using MrBayes, which indicated the presence of two isolates of the coral reef pathogen A. sydowii, as well as 16 additional species that are potentially pathogenic to corals. Although the analyzed gorgonian specimens appeared healthy, the presence of these pathogens, especially of A. sydowii, alert us to the potential risk to the health and future survival of the Pacific Ecuadorian coral ecosystem under the current scenario of increasing threats and stressors to coral reefs, such as habitat alterations by humans and global climate change.This research was only partially supported by a grant from the Spanish Ministry of Economy and Competitiveness (CTM2014-57949-R).Peer Reviewe

Potential impacts of climate variability on Dengue Hemorrhagic Fever in Honduras, 2010

Climate change and variability are affecting human health and disease direct or indirectly through many mechanisms. Dengue is one of those diseases that is strongly influenced by climate variability; however its study in Central America has been poorly approached. In this study, we assessed potential associations between macroclimatic and microclimatic variation and dengue hemorrhagic fever (DHF) cases in the main hospital of Honduras during 2010. In this year, 3,353 cases of DHF were reported in the Hospital Escuela, Tegucigalpa. Climatic periods marked a difference of 158% in the mean incidence of cases, from El Niño weeks (-99% of cases below the mean incidence) to La Niña months (+59% of cases above it) (p<0.01). Linear regression showed significantly higher dengue incidence with lower values of Oceanic Niño Index (p=0.0097), higher rain probability (p=0.0149), accumulated rain (p=0.0443) and higher relative humidity (p=0.0292). At a multiple linear regression model using those variables, ONI values shown to be the most important and significant factor found to be associated with the monthly occurrence of DHF cases (r2=0.649; βstandardized=–0.836; p=0.01). As has been shown herein, climate variability is an important element influencing the dengue epidemiology in Honduras. However, it is necessary to extend these studies in this and other countries in the Central America region, because these models can be applied for surveillance as well as for prediction of dengue

Incisivo lateral superior con dos raíces y dos conductos. Caso Clínico.

Las anomalías en la morfología del incisivo lateral superior son de muy baja frecuencia. Las anomalías de desarrollo radicular pueden presentarse como alteraciones tanto en el número de conductos, como en el número de raíces, así como en ambas regiones a la vez. En el presente trabajo, se reporta el caso de un paciente que se presenta a la consulta con malestar en el incisivo lateral superior izquierdo. En la radiografía preoperatoria se detectó la presencia de dos conductos y dos raíces, sin anomalía morfológica de su corona clínica, con requerimiento de tratamiento endodóntico. Concluimos que una correcta interpretación de las imágenes radiográficas preoperatorias es esencial, para poder detectar estas variantes y tomar las consideraciones necesarias para el adecuado tratamiento endodóntico.Fil: Martinez, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Boldo, M.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Corominola, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Sierra, L.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Lenarduzzi, A.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Fernández Solari, Jose Javier. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Fisiología; Argentina;Fil: Rodriguez, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina

Naturalistic driving study for older drivers based on the DriveSafe app

2019 IEEE Intelligent Transportation Systems Conference (ITSC), Auckland, New Zealand, 27-30 Oct. 2019Elderly population is increasing year after year in the developed countries. However, the knowledge of actual mobility needs of senior drivers is scarce. In this paper, we present a naturalistic driving study (NDS) focused on older drivers through smartphone technology and using our DriveSafe app. Our system automatically generates a driving analysis report based on objective indicators. The proposal supposes an improvement over the traditional surveys and observers, and represents an advance over the current NDSs by using smartphones instead of complex instrumented vehicles. Our method avoids the problems of manual annotation by using an automatic method for data reduction information. Furthermore, a comparison between traditional questionnaires and information provided by our system is carried out and conclusions are presented.Ministerio de Economía y CompetitividadDGTComunidad de Madri

Formal conceptualisation as a basic for a more procedural knowledge management

Knowledge management at an organisational level can only be brought into practice if a corporate memory is defined. Unfortunately, at this moment there is no complete and procedural specification on how to build it. This paper presents a complete and generic knowledge representation scheme that makes it possible to conceptualise/represent the knowledge of any domain in a systematic way, guiding the definition of a corporate memory and allowing us to reach a more procedural level in knowledge management discipline. The conclusions of our study, which follows the generic and formal definition of any conceptualisation, are illustrated by a real project