The insulation systems of equipment, cables, and electrical machines subjected to high voltage are continuously exposed to multiple aging mechanisms of electrical, mechanical, thermal, and ...environmental type. Normally, a failure in the material under these conditions does not occur immediately, but over time, different degradation processes emerge and evolve, progressively deteriorating the insulation, until breakdown occurs, and consequently, the asset finishes its operation with a catastrophic failure. In this context, partial discharge (PD) measurement can be considered as one of the best indicators when diagnosing the status of much electrical equipment in operation. However, the simultaneous presence of noise sources or multiple PD sources can generate important difficulties in identifying the type or types of sources measured. These practical limitations can be solved if, prior to the identification, a separation process is carried out, which allows classifying the different sources acting over the equipment being monitored. Once the sources separation is executed, the subsequent identification and diagnosis process can be carried out more easily. In this article, we present a novel separation technique based on the temporal and spectral behavior of the PD signals. For this technique, the separation of sources is carried out through three different parameters. Two of them are based on the peakedness of PD signals and electrical noise, and the third parameter is associated with their spectral content. Based on these parameters, a 3-D separation map is established, representing in clusters each source captured by the sensors.
Teleoperated robotics in recent years has proven to be valuable support in EOD tasks; a remarkable improvement in the systems that control these robots has been the Natural User Interfaces (NUI), ...allowing the use of simple gestures to control systems; however, the research that implements these type of systems do not focus on the stability of the robotic arm movements, necessary for this type of applications due to the danger of working with explosives. In this paper, we propose the implementation of an Optimal Signal Processing for a NUI interface based on Leap Motion that allows correct identification of the operator's intentional movements, high stability of the robotic gripper by suppressing the physiological tremors of the operator's hand, a greater facility for the execution of Explosive Ordnance Disposal (EOD) tasks, considering not to increase the mental workload nor to decrease the usability of the system. The signal processing proposed in this paper is composed of three filtering algorithms: Kalman, FIR, and moving average with a threshold. The results are compared with the most representative processing of recent research. To evaluate and validate the proposed signal processing, a target path tracking test is developed to evaluate the correct identification of the operator's intentional movements, a stability analysis of the robotic gripper, a performance analysis in the execution of Pick and Place tasks, NASA-TLX and SUS questionnaires to determine the mental workload and usability of the system, the proposed Optimal Signal Processing is implemented in the DOBOT-MAGICIAN and tested by police officers of the EOD Unit-Arequipa (UDEX-AQP); the results indicate a reduction in Average Vibration of 31.61% and Target Path Tracking error of 67.57%.
Premise
The genus Calceolaria (Calceolariaceae) is emblematic of the Andes, is hypothesized to have originated as a recent, rapid radiation, and has important taxonomic needs. Additionally, the genus ...is a model for the study of specialized pollination systems, as its flowers are nectarless and many offer floral oils as a pollination reward collected by specialist bees. Despite their evolutionary and ecological significance, obtaining a resolved phylogeny for the group has proved difficult. To address this challenge, we present a new bait set for targeted sequencing of nuclear loci in Calceolariaceae and close relatives.
Methods
We developed a bioinformatic workflow to use incomplete, low‐coverage genomes of 10 Calceolaria species to identify single‐copy loci suitable for phylogenetic studies and design baits for targeted sequencing.
Results
Our approach resulted in the identification of 809 single‐copy loci (733 noncoding and 76 coding regions) and the development of 39,937 baits, which we validated in silico (10 specimens) and in vitro (29 Calceolariaceae and six outgroups). In both cases, the data allowed us to recover robust phylogenetic estimates.
Discussion
Our results demonstrate the appropriateness of the bait set for sequencing recent and historic specimens of Calceolariaceae and close relatives, and open new doors for further investigation of the evolutionary history of this hyperdiverse genus.
In Chile, hydatidosis is endemic throughout the country and hyperendemic in some regions. It continues to be a public health problem that has been neglected and little addressed at the national ...level. In the Region of Libertador Bernardo O'Higgins, reported cases and hospital discharges still show high values, this area being representative of medium risk.
To estimate the risk of human hydatidosis in this region, studying the relationship of notifications and hospital discharge rates with social and environmental factors such as population, poverty index, schooling, literacy, average temperature, average rainfall and sheep population size.
Poisson regressions were used to study the factors associated with reported cases and hospital discharge rates and the BYM model for relative risk.
We found that the factors most related to absolute risk were the schooling index as a protective factor and the average temperatures as an enhancing factor. The sheep population size was also a relevant factor, especially when analyzing the distribution of relative risk. The areas of greatest risk in the region were La Estrella, Marchigue, Litueche, Santa Cruz and Lolol according to discharge rates, adding Pumanque and Peralillo according to notifications. These reveal a distribution of the zones of risk of hydatidosis towards the coastal mountain range in this region.
The more relevant factors associated to hydatidosis were schooling index, temperature an sheep population.
En el presente trabajo se realiza una aproximación interpretativa a las prácticas de educación comunitaria crítica de la extensión universitaria de la Universidad Surcolombiana, con base en los ...proyectos de Alfabetización del Pato Guayabero y el Macroproyecto DESCA; en el marco socio-histórico, contextualizado, situado y plural. Se reconocen las tensiones entre las posturas de la extensión universitaria y los contenidos de los proyectos en mención. Y, finalmente, se identifican seis prácticas de educación comunitaria crítica por sus saberes prácticos, sentires y materialidades.
Time-varying phenomena are one of the most substantial sources of astrophysical information, and led to many fundamental discoveries in modern astronomy. We have developed an automated tool to search ...and analyze variable sources in the near infrared Ks band, using the data from the Vista Variables in the Vía Láctea (VVV) ESO Public Survey (5, 8). One of our main goals is to investigate the Young Stellar Objects (YSOs) in the Galactic star forming regions, looking for: * • Variability. * • New pre-main sequence star clusters. Here we present the newly discovered YSOs within some selected stellar clusters in our Galaxy.
En la actualidad se observa un desarrollo vigoroso de la ciencia cognitiva, que es un campo multidisciplinario en el que confluyen varias disciplinas, como la psicología cognitiva, la inteligencia ...artificial, la lingüística, la filosofía, la neurociencia, la antropología cognitiva, entre otras, con la finalidad de estudiar la cognición. El estudio de la cognición y la mente se ha venido realizando desde el punto de vista de la filosofía estrictamente especulativa, desde la perspectiva de la filosofía de la mente y desde el punto de vista científico. Los aportes hipotéticos y/o teóricos de esos estudios de la mente son discutidos y, en la mayoría de los casos, sometidos a un análisis experimental para contrastar su validez científica. En ese sentido, la ciencia cognitiva ha ido estableciendo las propiedades esenciales de la mente y la cognición, tal como el carácter representacional de la mente, la relación causal entre la representación cognitiva y la conducta, el carácter simbólico de la información representada mentalmente, la mente como procesador de la información, la mente como un sistema de mecanismos, la modularidad de la mente, etc. Sin embargo, en la ciencia cognitiva actual es notoria la presencia de diferentes enfoques cognitivos que defienden el modelo simbólico clásico, por un lado, y por otro están aquellos que defienden el modelo conexionista o procesamiento distribuido en paralelo (PDP), y también aquellos que postulan modelos mentales no representacionalistas. En conclusión, se puede decir que hoy en día el estudio de la mente y la cognición es una empresa importante en el que están comprometidas varias disciplinas.
The Concept of the New Literature Gómez de la Serna, Ramón; Fernández-Medina, Nicolás
PMLA : Publications of the Modern Language Association of America,
01/2024, Letnik:
139, Številka:
1
Journal Article
Radial twin-entry turbines standard maps have limited data available for fitting model parameters since they usually provide information only at full and partial admission conditions. However, ...twin-entry turbines’ most common operation is at unequal admission conditions. A new losses-based efficiency model has been developed that takes into account the behaviour of the twin-entry turbines at unequal admission conditions considering the different losses produced in each of its parts to improve the model predictions in these conditions. The model is validated with experimental measurements of the whole range of admission conditions, and all the model parameters needed are fitted. Moreover, the model’s accuracy is compared with empirical and commercial models using a limited amount of data instead of the whole measured map, obtaining reasonable extrapolations and improving the results provided by the other models at unequal admission conditions.
•New losses-based 1D efficiency model developed for studying twin-entry turbines.•The sources of losses have been defined and modelled.•Momentum exchange between flow branches relevant under unequal admission conditions.•Efficiency model validated with experimental data at different admission conditions.•Modelled apparent and actual efficiency depend on mass flow ratio.•Model extrapolations with better predictions than empirical and commercial models.
NGC 6231 is a young cluster (age ∼2-7 Myr) dominating the Sco OB1 association (distance ∼1.59 kpc) with ∼100 O and B stars and a large pre-main-sequence stellar population. We combine a reanalysis of ...archival Chandra X-ray data with multiepoch near-infrared (NIR) photometry from the VISTA Variables in the Vía Lactéa (VVV) survey and published optical catalogs to obtain a catalog of 2148 probable cluster members. This catalog is 70% larger than previous censuses of probable cluster members in NGC 6231. It includes many low-mass stars detected in the NIR but not in the optical and some B stars without previously noted X-ray counterparts. In addition, we identify 295 NIR variables, about half of which are expected to be pre-main-sequence stars. With the more complete sample, we estimate a total population in the Chandra field of 5700-7500 cluster members down to 0.08 (assuming a universal initial mass function) with a completeness limit at 0.5 . A decrease in stellar X-ray luminosities is noted relative to other younger clusters. However, within the cluster, there is little variation in the distribution of X-ray luminosities for ages less than 5 Myr. The X-ray spectral hardness for B stars may be useful for distinguishing between early-B stars with X-rays generated in stellar winds and B-star systems with X-rays from a pre-main-sequence companion (>35% of B stars). A small fraction of catalog members have unusually high X-ray median energies or reddened NIR colors, which might be explained by absorption from thick or edge-on disks or being background field stars.
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