Search results for "internet"

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.

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…

A Self-Powered Long-range Wireless IoT Device based on LoRaWAN

2020

In this article, we propose a self-powered long-range wireless Internet-of-Things (IoT) device based on Long Range Wide Area Network (LoRaWAN) with various sensing capabilities. The nodes are designed based on ambient energy harvesting in such a way that these are self-sustainable throughout the components’ lifespan. Also, these nodes can be deployed on a large scale and are maintenance-free. In addition, these nodes can be deployed in remote places where the accessibility is limited, and maintenance is difficult. The wireless sensor nodes can be deployed both in indoor and outdoor environments with sufficient light levels for the solar panel, such as indoor lights in the indoor environment…

Service level guarantee framework for IoT environments

2017

Nowadays, providing IoT environments with service level guarantee is a challenging task. We propose a framework for IoT service level guarantee thanks to several specific Service Level Agreements (SLAs) for IoT environments. We specify different SLAs for each entity contributing in our IoT architecture in order to conclude a global SLA called IoT-SLA (iSLA). These different SLAs enable IoT service provision with Quality of Service (QoS) guarantee. Achieving this guarantee requires several communications and interactions between the components of the proposed IoT architecture. These interactions allow an IoT Service Provider (IoT-SP) to conclude the iSLA with an IoT Client (IoT-C). We specif…

Energy consumption and optimal relay node placement for cooperative retransmissions

2010

Previous work on cooperative MAC design has shown significant performance improvement in terms of throughput and packet delivery ratio. However, little attention has been paid to extra energy cost at the relay node in order to achieve such benefit. In this paper, we focus on analyzing energy consumption at a relay node in cooperative retransmission networks with mixed Rayleigh and Rician fading channels. Furthermore, optimal relay location is studied with respect to energy efficiency in different scenarios. The simulation and calculation results coincide with each other, both showing the optimal location of the relay node is scenario-dependent and can be obtained under given channel conditi…

Panel Summary: Frontiers of Human-Machine Interaction

2001

The hot points presented to the panel were the following: What are the broader definitions of Human/Machine interaction? For example: non direct connection (using currently available computer GUI) first phase direct connection (linking sensors to the sensory system) second phase (direct connections into the Central Nervous System) What are the technologies that should be developed in order to enable each of the previous phases? What are the scientific research issues that are related to such phases? What are the possible implications of a direct human-computer link on the society? (compared to the Internet revolution?) There are several phases in Human-Machine interaction. The first, and mo…

Interference Estimation in IEEE 802.11 Networks

2010

This article describes a technique for distinguishing and quantifying medium access control (MAC) and physical layer (PHY) interference in error-prone 802.11 networks. This technique, is fully distributed, allowing each station to estimate interference individually. The estimator is based on an extended Kalman filter coupled to a mechanism for revealing abrupt changes in state. The network state is a vector of two components, representing PHY interference, expressed in terms of channel-error rate, and MAC interference. Two distinct state models are considered. When PHY interference can be assumed to be constant for all stations, network congestion is expressed by the number of competing ter…

Introduction to the Minitrack on Software Development for Mobile Devices, the Internet-of-Things, and Cyber-Physical Systems

2021

Visualising knowledge from chat debates in argument diagrams

2010

This study investigates whether combining chat discussion and construction of an argument diagram stimulates students to formulate new ideas in practising argumentation. In this study, 16 secondary school students discussed vivisection and gender equality in pairs using both free and structured chat tools. In structured chat, the students selected and completed partial sentences provided by the computer. After the discussion, they jointly constructed either argument diagrams freely based on the previous discussions with an Internet tool or modified a diagram the computer had constructed automatically during the structured chat. The freely constructed diagrams contained more of the students'…

A Novel Amplify-and-Forward Relay Channel Model for Mobile-to-Mobile Fading Channels under Line-of-Sight Conditions

2021

In this chapter, we have proposed a new flexible M2M amplify-and-forward relay fading channel model under LOS propagation conditions. The novelty in the model is that we have considered the LOS components in both transmission links, i.e., the direct link between the source mobile station and the destination mobile station as well as the link via the mobile relay. By analogy with multiple scattering radio propagation channels, we have developed the MLSS fading channel as a second-order scattering channel, where the received signal comprises the single and double scattered components. Furthermore, the flexibility of the MLSS fading channel model comes from the fact that it can be reduced to d…