3,767 research outputs found
Pairing-based authentication protocol for V2G networks in smart grid
[EN] Vehicle to Grid (V2G) network is a very important component for Smart Grid (SG), as it offers new services that help the optimization of both supply and demand of energy in the SG network and provide mobile distributed capacity of battery storage for minimizing the dependency of non-renewable energy sources. However, the privacy and anonymity of users¿ identity, confidentiality of the transmitted data and location of the Electric Vehicle (EV) must be guaranteed. This article proposes a pairing-based authentication protocol that guarantees confidentiality of communications, protects the identities of EV users and prevents attackers from tracking the vehicle. Results from computing and communications performance analyses were better in comparison to other protocols, thus overcoming signaling congestion and reducing bandwidth consumption. The protocol protects EVs from various known attacks and its formal security analysis revealed it achieves the security goals.Roman, LFA.; Gondim, PRL.; Lloret, J. (2019). Pairing-based authentication protocol for V2G networks in smart grid. Ad Hoc Networks. 90:1-16. https://doi.org/10.1016/j.adhoc.2018.08.0151169
Critical boron-doping levels for generation of dislocations in synthetic diamond
Defects induced by boron doping in diamond layers were studied by transmission electron microscopy. The existence of a critical boron doping level above which defects are generated is reported. This level is found to be dependent on the CH4
/H2 molar ratios and on growth directions. The critical boron concentration lied in the 6.5–17.0 X 10 20 at/cm3 range in the direction and at 3.2 X 1021 at/cm
3 for the one. Strain related effects induced by the doping are shown not to
be responsible. From the location of dislocations and their Burger vectors, a model is proposed, together with their generation mechanism.6 page
SDN-DMM for intelligent mobility management in heterogeneous mobile IP networks
[EN] Mobility management applied to the traditional architecture of the Internet has become a great challenge because of the exponential growth in the number of devices that can connect to the network. This article proposes a Software-Defined Networking (SDN)-based architecture, called SDN-DMM (SDN-Distributed Mobility Management), that deals with the distributed mode of mobility management in heterogeneous access networks in a simplified and efficient way, ensuring mainly the continuity of IP sessions. Intent-based mobility management with an IP mapping schema for mobile node identification offers optimized routing without tunneling techniques, hence, an efficient use of the network infrastructure. The simplified mobility control API reduces both signaling and handover latency costs and provides a better scalability and performance in comparison with traditional and SDN-based DMM approaches. An analytical evaluation of such costs demonstrated the better performance of SDN-DMM, and a proof of concept of the proposal was implemented in a real environment.CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior) - Brasil; Secretaria de Estado de Investigacion, Desarrollo e Innovacion, Grant/Award Number: TIN2017-84802-C2-1-P; "Convocatoria 2017 - Proyectos I+D+I Programa Estatal de Investigacion, Desarrollo e Innovacion, convocatoria excelencia", Grant/Award Number: TIN2017-84802-C2-1-P; FAP-DF ("Fundacao de Apoio a Pesquisa do Distrito Federal")-BrazilTorres Cordova, R.; Gondim, PRL.; Llerena, YP.; Lloret, J. (2019). SDN-DMM for intelligent mobility management in heterogeneous mobile IP networks. International Journal of Communication Systems. 32(17):1-31. https://doi.org/10.1002/dac.4140131321
An automated model for the assessment of QoE of adaptive video streaming over wireless networks
[EN] Nowadays, heterogeneous devices are widely utilizing Hypertext Transfer Protocol (HTTP) to transfer the data. Furthermore, HTTP adaptive video streaming (HAS) technology transmits the video data over wired and wireless networks. In adaptive technology services, a client's application receives a streaming video through the adaptation of its quality to the network condition. However, such a technology has increased the demand for Quality of Experience (QoE) in terms of prediction and assessment. It can also cause a challenging behavior regarding subjective and objective QoE evaluations of HTTP adaptive video over time since each Quality of Service (QoS) parameter affects the QoE of end-users separately. This paper introduces a methodology design for the evaluation of subjective QoE in adaptive video streaming over wireless networks. Besides, some parameters are considered such as video characteristics, segment length, initial delay, switch strategy, stalls, as well as QoS parameters. The experiment's evaluation demonstrated that objective metrics can be mapped to the most significant subjective parameters for user's experience. The automated model could function to demonstrate the importance of correlation for network behaviors' parameters. Consequently, it directly influences the satisfaction of the end-user's perceptual quality. In comparison with other recent related works, the model provided a positive Pearson Correlation value. Simulated results give a better performance between objective Structural Similarity (SSIM) and subjective Mean Opinion Score (MOS) evaluation metrics for all video test samples.This work has been partially supported by the "Ministerio de Economia y Competitividad" in the "Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia, Subprograma Estatal de Generacion de Conocimiento" within the Project under Grant TIN2017-84802-C2-1-P. This study has been partially done in the computer science departments at the (University of Sulaimani and Halabja).Taha, M.; Ali, A.; Lloret, J.; Gondim, PRL.; Canovas, A. (2021). An automated model for the assessment of QoE of adaptive video streaming over wireless networks. Multimedia Tools and Applications. 80(17):26833-26854. https://doi.org/10.1007/s11042-021-10934-92683326854801
Secret sharing-based authentication and key agreement protocol for machine-type communications
[EN] One of the main challenges for the development of the Internet of Things is the authentication of large numbers of devices/sensors, commonly served by massive machine-type communications, which jointly with long-term evolution has been considered one of the main foundations for the continued growth of Internet of Things connectivity and an important issue to be treated in the development of 5G networks. This article describes some protocols for the group-based authentication of devices/sensors in Internet of Things and presents a new group authentication protocol based on Shamir's secret and Lagrange interpolation formula. The new protocol protects privacy, avoids unauthorized access to information, and assists in the prevention of attacks, as replay, distributed denial of service, and man-in-the-middle. A security analysis and comparisons among the 3GPP evolved packet system authentication and key agreement standard protocol and other recent group authentication protocols were performed toward proving the efficiency of the proposed protocol. The comparisons regard security properties and computational and communication costs. The safety of the protocol was formally verified through simulations conducted by automated validation of internet security protocols and applications.Lopes, APG.; Hilgert, LO.; Gondim, PRL.; Lloret, J. (2019). Secret sharing-based authentication and key agreement protocol for machine-type communications. International Journal of Distributed Sensor Networks (Online). 15(4):1-21. https://doi.org/10.1177/1550147719841003S12115
Little “We’s”: how common identities improve behavior differently for ethnic majority and minority children
This field experiment tested whether inducing common inclusive representations (i.e., one group, dual identity) during contact influences intergroup relations differently for ethnic majority and minority children by changing their metaperceptions and intergroup emotions differently. White (N = 113) and Black (N = 111) 8- to 10-year-old children were exposed to interactive mixed-ethnicity sessions in schools emphasizing either categorization as one group (national group), dual identity (national group with ethnic subgroups), or two ethnic groups. Overall, as predicted, for White children, one-group, but not dual-identity perceptions, improved behavioral intentions by influencing metaperceptions. For Black children, dual-identity, but not one-group, perceptions improved behavioral intentions through metaperceptions. Contrary to the expected, both dual-identity and one-group perceptions were associated with White and Black children’s intergroup emotions.info:eu-repo/semantics/acceptedVersio
Efectos de la nutrición mineral sobre la eficiencia en el uso del agua de verdeos de invierno
La nutrición mineral tiene una influencia positiva sobre la eficiencia en el uso del agua de verdeos de invierno, en relación a la producción de materia seca y la calidad de la misma. El desplazamiento de la ganadería por la agricultura hacia suelos con menor potencial estaría condicionando una menor eficiencia en el uso del agua para la producción de forraje y carne en los sistemas mixtos. Se planteó como objetivo de trabajo evaluar el efecto de la nutrición mineral (N,P) sobre la producción de forraje y eficiencia en el uso del agua en centeno establecido en un Haplustol Éntico con contenidos medios a bajos de MO y P disponible. Para llevar a cabo la experiencia se hizo un diseño de tres bloques, cada uno contó con nueve tratamientos de fertilización (N-P), utilizando parcelas de 150 m^ (10 X 15m). Se establecieron tres tratamientos de fertilización nitrogenada (N0= Okg/ha; N40= 40kg/ha y N80= 80l<gN/ha) utilizando urea granulada, aplicada "al voleo" (29/03/06) y tres tratamientos con fertilización fosforada (P0= Okg/ha; P100= 100kg/ha; P200= 200kg/ha) realizada a la siembra, con superfosfato triple de calcio como fuente de fósforo. El suelo de textura franco arenosa, con 41% de arcilla + timo, presentó contenidos de 1,7% de MO y 9 ppm de P en los primeros 20cm del perfil. La profundidad media de la tosca resultó de 80cm, dando lugar a una capacidad de retención de agua de 187mm. El uso consuntivo del verdeo resultó de 227 y 230mm de agua para los tratamientos extremos de fertilización, NO y N80 respectivamente. Se comprobó interacción significativa N-P. No existió efecto de fósforo si no hay aplicación de nitrógeno. Las dos dosis de fósforo (100 y 200) difirieron de la dosis PO cuando se aplicó N 40, mientras que cuando se aplicó N 80, todas las comparaciones entre dosis de fósforo difirieron entre si (p < 0,001). Similar comportamiento se registró con N, resultando la respuesta dependiente de la fertilización fosforada. La eficiencia en el uso del agua se incrementó significativamente desde 10,6 kg/ha.mm de materia seca para el testigo hasta 21,8 kg/ha.mm para el tratamiento de máxima fertilización. Los resultados permiten inferir la pérdida de eficiencia de la producción de forraje, en la medida que los suelos comparativamente de mayor fertilidad son asignados a la agricultura, y la necesidad de incrementar los costos por uso de fertilizantes para mantener niveles de eficiencia en la producción.Director: Dr. Alberto Quirog
Comparación in vitro de la acción fungicida de solución saturada de azúcar y nitrato de econazol
En investigaciones previas realizadas in vitro con solución saturada de sacarosa, eugenol y polietilenglicol 400 secomprobó su eficacia fungicida sobre Candida albicans.Se comparó en las mismas condiciones el efecto fungicida con nitrato de econazol. Una suspensión de Candidaalbicans con nitrato de econazol se repicó en Agar Sabouraud 20 a distintos tiempos para demostrar la viabilidadde la cepa.El tiempo promedio de muerte de Candida albicans en la solución saturada de sacarosa fue de 300 segundos, ennitrato de econazol fue de pocos segundos.Aunque existen diferencias significativas en el tiempo de muerte de la cepa ensayada, la solución saturada desacarosa sería una contribución terapéutica alternativa, en aquellos pacientes con lesiones cutáneas crónicas que noresponden a los tratamientos tradicionales
Intensidad de texturas vs espesores en Aleaciones de Zinc-Níquel + Micropartículas de Alúmina. Caracterización del material (Dureza, Contenido de Níquel %, XRD, AFM, SEM, FRX, EIS)
The metallic coating of zinc alloyed with other metals such as nickel, has very good corrosion resistance. It was found that the type and quantity of particles, increases the hardness and the nickel content in the alloy at all current densities. Photomicrographs were made in electronic and optical microscope (in samples with particle, cross sectional views). We have found that there is an optimum thickness of 10 microns in which the intensity of texture in the material is increased. In this thickness in ZnNi - Al2O3, the Charge Transference Resistance, RTC in ohm, measured by Impedance was RTC ZnNi + Al2O3 > RTC ZnNi and in the Polarization Curves the corrosion current density is decreased. In salt spray tests on samples with the same thickness, it was found that the area with white rust is lower for Zn Ni with Al2O3 on the affected area that in other cases.Fil:Mahmud, Z. Instituto Nacional de Tecnología Industrial (INTI)Fil:Amelotti, F. Instituto Nacional de Tecnología Industrial (INTI)Fil:Lloret, P. Instituto Nacional de Tecnología Industrial (INTI)Fil:Gagliardi, J. Instituto Nacional de Tecnología Industrial (INTI)Fil:Túlio, P. Universidade Tecnológica Federal do Paraná (UTFPR)Fil:Míngolo, N. Comisión Nacional de Energía Atómica (CNEA)Fil:Gassa, L. Universidad Nacional de La Plata (UNLP). Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y AplicadasFil:Gordillo, G. Universidad de Buenos Aires (UBA). Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Físic
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