58,802 research outputs found
Evaluating the more suitable ISM frequency band for iot-based smart grids: a quantitative study of 915 MHz vs. 2400 MHz
IoT has begun to be employed pervasively in industrial environments and critical infrastructures thanks to its positive impact on performance and efficiency. Among these environments, the Smart Grid (SG) excels as the perfect host for this technology, mainly due to its potential to become the motor of the rest of electrically-dependent infrastructures. To make this SG-oriented IoT cost-effective, most deployments employ unlicensed ISM bands, specifically the 2400 MHz one, due to its extended communication bandwidth in comparison with lower bands. This band has been extensively used for years by Wireless Sensor Networks (WSN) and Mobile Ad-hoc Networks (MANET), from which the IoT technologically inherits. However, this work questions and evaluates the suitability of such a "default" communication band in SG environments, compared with the 915 MHz ISM band. A comprehensive quantitative comparison of these bands has been accomplished in terms of: power consumption, average network delay, and packet reception rate. To allow such a study, a dual-band propagation model specifically designed for the SG has been derived, tested, and incorporated into the well-known TOSSIM simulator. Simulation results reveal that only in the absence of other 2400 MHz interfering devices (such as WiFi or Bluetooth) or in small networks, is the 2400 MHz band the best option. In any other case, SG-oriented IoT quantitatively perform better if operating in the 915 MHz band.This research was supported by the MINECO/FEDER project grants TEC2013-47016-C2-2-R (COINS) and TEC2016-76465-C2-1-R (AIM). The authors would like to thank Juan Salvador Perez Madrid nd Domingo Meca (part of the Iberdrola staff) for the support provided during the realization of this work. Ruben M. Sandoval also thanks the Spanish MICINN for an FPU (REF FPU14/03424) pre-doctoral fellowship
Ébola in TChM: Diagnosis, Principles of Treatment and Economical Analysis
InvestigaciĂłn sobre etiologĂa y tratamiento con MTC del Ă©bola, especial referencia al entorno econĂłmicoIn this research we go more deeply into EVD, studying the Etiology and realizing a Differentiation of Syndromes according to the systems: Wen Bing, San Jiao and Han Shan Lun. Later, a Treatment for Prevention, Symptomatic/Acute, and Remission phases is proposed. Finally, we study the economic effects of the epidemic in the most affected countries by stressing the importance of preventive health care and international aid, looking at the usefulness of Medical Matter for its low cost especially in the affected societies (that probably they will return to be).Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Electrorotation of semiconducting microspheres
We study experimentally the electrorotation (ROT) of semiconducting microspheres. ZnO microspheres obtained by a hydrothermal synthesis method are dispersed in KCl aqueous solutions and subjected to rotating electric fields. Two ROT peaks are found in experiments: a counterfield peak and a cofield peak at somewhat higher frequencies. These observations are in accordance with recent theoretical predictions for semiconducting spheres. The counterfield rotation is originated by the charging of the electrical double layer at the particle-electrolyte interface, while the cofield rotation is due to the Maxwell-Wagner relaxation. Additionally, we also found that some microspheres in the sample behaved differently and only showed counterfield rotation. We show that the behavior of these particles can be described by the so-called shell model. The microstructure of the microspheres is analyzed with electron microscope techniques and related to the ROT measurements.Spanish Government Ministry MICINN under Contract No. PGC2018-099217-B-I00Junta de AndalucĂa Contract No. PEJUS-
Self-Referencing Fiber-Optic Intensity Sensors Using Ring Resonators and Fiber Bragg Gratings
An improved ring resonator self-referencing technique in a new reflection configuration for remote fiber-optic intensity sensors is demonstrated using fiber Bragg gratings. Sensor sensitivity doubles and a single fiber lead is used. The sensor is interrogated at two subcarrier frequencies having a high rejection of interference from laser source intensity fluctuations and loss in the fiber lead. We experimentally demonstrate the efficiency of the new reflection configuration, the usefulness of the theoretical model proposed, and discuss design parameters for optimum insertion lossesThis work was supported in part by CICYT (TIC2003-03783 and TEC2006-13273-C03-03-MIC), in part by UC3M (FAVICOBIS), in part by CAM (FACTOTEM-CM:S-0505/ESP/000417), and in part by COST 299.Publicad
On curves with one place at infinity
Let be a plane curve. We give a procedure based on Abhyankar's
approximate roots to detect if it has a single place at infinity, and if so
construct its associated -sequence, and consequently its value
semigroup. Also for fixed genus (equivalently Frobenius number) we construct
all -sequences generating numerical semigroups with this given genus.
For a -sequence we present a procedure to construct all curves having
this associated sequence.
We also study the embeddings of such curves in the plane. In particular, we
prove that polynomial curves might not have a unique embedding.Comment: 14 pages, 2 figure
Spin Analysis of the Process e+e- --> tau+tau- at LEP
Using the data collected by the four experiments at LEP during 1990-1994, a
precise measurement of the tau longitudinal polarisation (P_tau) has been
performed, as well as the measurement of the transverse-transverse and
transverse-normal tau spin correlations. From the P_tau measurement, assuming
lepton universality of the neutral currents, the effective weak mixing angle
has been determined to be sin(theta_W) = 0.2325 +- 0.0006. The Standard Model
predictions are consistent with the measured results.Comment: Invited talk to San Miniato 1997, 6 pages, 10 figures, Latex, macro
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