4,332 research outputs found
The mechanism why colliders could create quasi-stable black holes
It has been postulated that black holes could be created in particle
collisions within the range of the available energies for nowadays colliders
(LHC). In this paper we analyze the evaporation of a type of black holes that
are candidates for this specific behaviour, namely, small black holes on a
brane in a world with large extra-dimensions. We examine their evolution under
the assumption that energy conservation is satisfied during the process and
compare it with the standard evaporation approach. We claim that, rather than
undergoing a quick total evaporation, black holes become quasi-stable. We
comment on the (absence of) implications for safety of this result. We also
discuss how the presence of black holes together with the correctness of the
energy conservation approach might be experimentally verified.Comment: 16 pages, 3 figure
En cirurgia de còlon, són realment necessaris els antibiòtics orals?
Abans de sotmetre al pacient a una cirurgia de còlon li són administrats sistemàticament antibiòtics orals. És necessària aquesta medicació? Investigadors de l'Hospital Vall d'Hebron i la UAB creuen que no. Aquesta negativa categòrica reflecteix els resultats d'un estudi en què van participar 300 persones sotmeses a aquesta invervenció.Antes de someter al paciente a una cirugía de colon se le administran sistemáticamente antibióticos orales. Pero, ¿realmente es necesaria esta medicación? Investigadores del Hospital Vall d'Hebron y la UAB creen que no. Esta tajante negativa refleja los resultados de un estudio en el que participaron 300 personas sometidas a esta intervención
Mucus and ciliated cells of human lung : splitting strategies for particle methods and 3D stokes flows
Lung walls are covered by a film of mucus, whose motility is fundamental for a healthy behavior. Indeed, mucus traps inhaled aerosols (bacteria, dust, ...), and moves from smallest to largest airways, until it reaches esophagus where is it swallowed or expectorated. A lot of biological parameters are responsible for mucus motion [6], such as the vibrations of ciliated cells covering lung walls (cilia height, frequency, ...), mucus/air interaction, water saturation in mucin network, mucus thickness
Linguistic Interpretation of Mathematical Morphology
Mathematical Morphology is a theory based on geometry, algebra, topology and set theory, with strong application to digital image processing. This theory is characterized by two basic operators: dilation and erosion. In this work we redefine these operators based on compensatory fuzzy logic using a linguistic definition, compatible with previous definitions of Fuzzy Mathematical Morphology. A comparison to previous definitions is presented, assessing robustness against noise.Fil: Bouchet, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Meschino, Gustavo. Universidad Nacional de Mar del Plata; ArgentinaFil: Brun, Marcel. Universidad Nacional de Mar del Plata; ArgentinaFil: Espin Andrade, Rafael. Instituto Superior Politécnico José Antonio Echeverría Cujae; CubaFil: Ballarin, Virginia. Universidad Nacional de Mar del Plata; Argentin
Data Validation and reconstruction for performance enhancement and maintenance of water networks
In a real water network, a telecontrol system must periodically acquire, store and validate data gathered by sensor measurements in order to achieve accurate monitoring of the whole network in real time. For each sensor measurement, data are usually represented by one-dimensional time series. These values, known as raw data, need to be validated before further use to assure the reliability of the results obtained when using them. In real operation, problems affecting the communication system, lack of reliability of sensors, or other inherent errors often arise, generating missing or false data during certain periods of time. These wrong data must be detected and replaced by estimated data. Thus, it is important to provide the data system with procedures that can detect such problems and assist the user in monitoring and processing the incoming data. Data validation is an essential step to improve data reliability. The validated data represent measurements of the variables in the required form where unnecessary information from raw data has been removed. In this paper, a methodology for data validation and reconstruction of sensor data in a water network is used to analyze the performance of the sectors of a water network. Finally, from this analysis several indicators of the components (sensors, actuators and pipes) and of the sectors themselves can be derived in order to organize useful plans for performance enhancement and maintenance. Nice practices have been developed during a large period in the water network of the company ATLL Concessionària de la Generalitat de Catalunya, S.A.Postprint (author's final draft
An improved tool of water data analytics for flowmeters data
This paper presents an improved tool for data validation and reconstruction of flowmeters. These sensors are installed in the Catalonia regional water network from Barcelona (Spain). Here a new time series model with exogenous variable is proposed with excellent results for data validation. It is postulated that the integration of the electronics alarms, along with other tests about the daily data accumulated and a later analysis of the data reconstruction allow to improve the results of the existing tools. This is accomplished by decreasing the false alarms and missing alarms of more than 6000 hourly data retrieved from more than 200 flowmeters each day. This new tool provides reliable information daily reliable information of the state of the water network. This information could potentially contribute to optimally control and manage this large and complex water network.Postprint (published version
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