Search results for "access"
showing 10 items of 1232 documents
Security, Reliability and Usability of mHealth Environments
2015
Mobile technologies confer mobility and autonomy on patients with the advantage of access to home care and health care services on demand. However, these benefits impose challenges to the future health care services. For instance, computation capacity of a conventional smartphone provides applications and services with sufficient power of calculation and automation to assist in daily life activities and medical purposes. Combined with a user-friendly interface, mobile technologies can be an easy and efficient manner to help people who are in a condition of cognitive deterioration or have a chronic disease which demands a close connection to near family members and/or to health care services.
Security in mobile agent systems
2007
DTMC modeling for performance evaluation of DW-MAC in wireless sensor networks
2016
Synchronized duty cycling (DC) aligns sensor nodes to wake up at the same time in order to reduce idle listening for medium access control (MAC) in wireless sensor networks (WSNs). Demand wakeup MAC (DW-MAC) is a popular synchronous DC MAC protocol which allows nodes to compete and transmit multiple packets in one operational cycle. This multiple packet transmission (MPT) feature makes DW-MAC more energy efficient when comparing with other existing single time competition based protocols such as sensor MAC (S-MAC). In the literature, no analytical model exists to evaluate the performance of DW-MAC. In this paper, we develop two associated discrete time Markov chain (DTMC) models and incorpo…
Temporal Fairness Provisioning in Multi-Rate Contention-Based 802.11e WLANs
2005
The IEEE 802.11e extensions for QoS support in WLAN define the transmission opportunity (TXOP) concept, in order to limit the channel holding times of the contending stations in the presence of delay-sensitive traffic. We evaluate the use of TXOP for a different purpose: "temporal fairness" provisioning among stations employing different data rates. We show that the equalization of the channel access times allows each station to obtain its throughput basically (1) proportional to its transmission rate, and (2) independent of the transmitted frame length. This also improves the aggregate throughput of the overall WLAN. For a given TXOP limit, i.e., a granted channel access time, a station is…
A Latent Class Analysis of Spanish Travelers’ Mobile Internet Usage in Travel Planning and Execution
2014
A study of 476 Spanish travelers found mixed interest and use for the many travel-related mobile internet services that are involved in planning and executing a trip. The findings indicate that these Spanish respondents can be classified into four segments based on the timing of using mobile apps for over a dozen activities involved in travel planning and execution: Savvies, Planners, Opportunists, and Low-techs. Each segment exhibits distinct patterns of mobile internet services usage. Savvies tend to be heavy mobile device users both before and during their trip, while Planners make heavy use of mobile devices in advance of but not during their trip. The Opportunists show a pattern oppos…
Cooperative Medium Access Control in Wireless Networks: The Two-Hop Case
2009
Cooperative communication has been recently proposed as a powerful means to improve network performance in wireless networks. However, most existing work focuses solely on one-hop source-destination cooperation. In this paper, we propose a novel cooperative MAC mechanism that is specially designed for two-hop cooperation communications where the source node and the destination node cannot hear each other directly. In this case, cooperative communication is operated in a two-hop manner and transmit-diversity is achieved by the reception of the same data packet forwarded through multiple relays towards a single destination. The proposed scheme employs an efficient relay selection algorithm to…
HSDPA Link Adaptation Improvement Based on Node-B CQI Processing
2007
In this paper HSDPA link adaptation (LA) based on Channel Quality Indicator (CQI) reports is optimised. A pre-processing of the last received CQI reports is done before the execution of the LA algorithm in the Node-B in order to obtain more profitable channel quality estimations and hence improve the LA performance. Different types of processing techniques are presented and assessed, considering from the simplest sample averaging to some more elaborated predictive algorithms. Results demonstrate that a non negligible enhancement in the LA performance can be obtained if medium and high speed users are considered.
Public Access Defibrillation
2000
Accesible co-creation tools for people with intellectual disabilities: working for and with end-users
2019
In a world defined by rapid change, the search for solutions to societal challenges has become more complex calling for new paradigms of innovation focused on collaborations with the community and users. Co-creation approaches in the design and production of a service or product can bring low-cost innovation and unique and personalized customer experiences leading to user acceptance of a product or service. Under a co-creation perspective, the participatory approach developed in the MINDInclusion project aims to improve the inclusion of people with intellectual disabilities into public places and society by using a co-created online tool based on people with disabilities’ personal experienc…
Good Intentions, Bad Results: The Effects of Newspaper Subsidies on Journalistic Quality
2013
News media play an irreplaceably important role in the successful working of democratic societies: they guarantee that citizens have access to information, are accurately informed, and actively take part in the political process. A crucial factor for the effective fulfillment of these democratic functions is an adequate level of journalistic quality.