Search results for " Network"
showing 10 items of 6428 documents
Analysis of RRM limitations and restricted transmission periods for VoIP over HSDPA
2009
This paper studies how the performance of Voice over IP (VoIP) over High Speed Downlink Packet Access (HS-DPA) networks is affected if transmission to a User Equipment (UE) is stopped for specific amount of time during handover procedure. This paper also addresses the situation when it might be necessary to limit the number of UEs in a cell. The study showed that parameter settings for Radio Resource Management (RRM) algorithms can have an effect to the VoIP capacity: If handover lasts long enough for VoIP packets to be lost, or severe congestion occurs in a cell, VoIP capacity may be degraded.
Analysis of VoIP over HSDPA Performance with Discontinuous Reception Cycles
2009
The aim of this paper is to evaluate how Discontinuous Reception (DRX) cycles and related timers take effect to Voice over IP (VoIP) performance when High Speed Downlink Packet Access (HSDPA) networks are in question. DRX cycles limit the scheduling freedom of users and increase battery saving opportunities in the User Equipment (UE) by allowing it to turn its receiver circuitry off for some periods of time. Prior work has concentrated mainly on optimizing the usage of radio resources when small bit rate delay critical services, like VoIP, are considered. However, the battery life of small handheld devices might become a limiting factor in providing satisfactory user experience. Thus, this …
Classification of diabetes-related retinal diseases using a deep learning approach in optical coherence tomography
2019
Background and objectives: Spectral Domain Optical Coherence Tomography (SD-OCT) is a volumetric imaging technique that allows measuring patterns between layers such as small amounts of fluid. Since 2012, automatic medical image analysis performance has steadily increased through the use of deep learning models that automatically learn relevant features for specific tasks, instead of designing visual features manually. Nevertheless, providing insights and interpretation of the predictions made by the model is still a challenge. This paper describes a deep learning model able to detect medically interpretable information in relevant images from a volume to classify diabetes-related retinal d…
Consentimiento de los menores de edad en las redes sociales: especial referencia Tiktok
2022
RESUMEN. El uso masificado de las redes sociales trae consigo una ingente cantidad de consecuencias jurídicas tanto en el ámbito del derecho de los contratos, como en materia de protección de datos, así como en el ámbito del derecho de los consumidores. Más de la mitad de la población mundial hace uso de este tipo de plataformas digitales y, en especial, un colectivo que merece una especial protección por parte de los legisladores: los menores de edad. Tras un análisis de la normativa aplicable a los menores de edad en las redes sociales se hace alusión, de una manera más tangible, al uso de la red social de TikTok por este colectivo. ABSTRACT. The massive use of social networks brings with…
Health as an Institutional Commitment. Reconversion of Nordkraft from a Power Station to a Cultural and Health Center
2021
The goal of public health prevention is not only to increase life expectancy, but also to improve the quality of life. It is therefore necessary to highlight the importance of the social opportunities available to the individual, that is, the ability to build relationships, cultivate interests, attend cultural events and lead a healthy lifestyle. Urban habitats, the main environments for socializing but also for spreading contagion (as the Covid-19 pandemic highlighted), must be remodelled to ensure public health. To achieve this goal, urban habitats must also be able to offer spaces for safe relationships to promote sociability and stimulate civic activism. The paper refers to the commitme…
One size hardly fits all
2013
This paper casts recent accomplishments in the field of Wireless MAC programmability into the emerging Software Defined Networking perspective. We argue that an abstract (but formal) description of the MAC protocol logic in terms of extensible finite state machines appears a convenient and viable data-plane programming compromise for modeling and deploying realistic MAC protocol logics. Our approach is shown to comply with existing control frameworks, and entails the ability to dynamically change the MAC protocol operation based on context and scenario conditions; in essence, move from the traditional idea of "one-size-fits-all" MAC protocol stack to the innovative paradigm of opportunistic…
MAClets: Active MAC Protocols over hard-coded devices
2012
We introduce MAClets, software programs uploaded and executed on-demand over wireless cards, and devised to change the card's real-time medium access control operation. MAClets permit seamless reconfiguration of the MAC stack, so as to adapt it to mutated context and spectrum conditions and perform tailored performance optimizations hardly accountable by an once-for-all protocol stack design. Following traditional active networking principles, MAClets can be directly conveyed within data packets and executed on hard-coded devices acting as virtual MAC machines. Indeed, rather than executing a pre-defined protocol, we envision a new architecture for wireless cards based on a protocol interpr…
Metric Learning in Histopathological Image Classification: Opening the Black Box
2023
The application of machine learning techniques to histopathology images enables advances in the field, providing valuable tools that can speed up and facilitate the diagnosis process. The classification of these images is a relevant aid for physicians who have to process a large number of images in long and repetitive tasks. This work proposes the adoption of metric learning that, beyond the task of classifying images, can provide additional information able to support the decision of the classification system. In particular, triplet networks have been employed to create a representation in the embedding space that gathers together images of the same class while tending to separate images w…
A Novel Wireless Sensor Network for Electric Power Metering
2013
Wireless sensor network with lightweight and efficient communication infrastructures are today a great interest, both at research and industrial level, as they are the basis for reliable monitoring services. Mesh networks are ideal candidates in this scenario, as they can be very fault-tolerant. After introducing wireless network systems requirements, we show the design of a mesh network routing protocol based on AODV schemas. Its implementation runs on top of low-cost off-the-shelf components, and allowed us to build a custom power meter wireless sensor node.
Aging Effects in a Lennard-Jones Glass
1997
Using molecular dynamics simulations we study the out of equilibrium dynamic correlations in a model glass-forming liquid. The system is quenched from a high temperature to a temperature below its glass transition temperature and the decay of the two-time intermediate scattering function C(t_w,t+t_w) is monitored for several values of the waiting time t_w after the quench. We find that C(t_w,t+t_w) shows a strong dependence on the waiting time, i.e. aging, depends on the temperature before the quench and, similar to the case of spin glasses, can be scaled onto a master curve.