Search results for "source"
showing 10 items of 6139 documents
A Comparative Eye Tracking Study of Usability—Towards Sustainable Web Design
2021
Websites are one of the most frequently used communication environments, and creating sustainable web designs should be an objective for all companies. Ensuring high usability is proving to be one of the main contributors to sustainable web design, reducing usage time, eliminating frustration and increasing satisfaction and retention. The present paper studies the usability of different website landing pages, seeking to identify the elements, structures and designs that increase usability. The study analyzed the behavior of 22 participants during their interaction with five different landing pages while they performed three tasks on the webpage and freely viewed each page for one minute. Th…
Essential oil crops for sustainable agriculture - A review
2009
Multifunctionality and diversification of farming systems, integration of agricultural practices both inter se and with the non-agricultural productive systems operating on the territory, biodiversity safeguards, and reduction in off-farm inputs, are key factors for all modern development strategies in agricultural areas. Such issues are valid worldwide, but are especially true in areas in which the cultivation of the more widespread and “classical” crops is constrained by factors of varying degree and importance. In Mediterranean areas, where many environmental and economic factors often reduce rural areas to marginal conditions, the search for new crop opportunities has become one of the …
Learn to Cache: Machine Learning for Network Edge Caching in the Big Data Era
2018
The unprecedented growth of wireless data traffic not only challenges the design and evolution of the wireless network architecture, but also brings about profound opportunities to drive and improve future networks. Meanwhile, the evolution of communications and computing technologies can make the network edge, such as BSs or UEs, become intelligent and rich in terms of computing and communications capabilities, which intuitively enables big data analytics at the network edge. In this article, we propose to explore big data analytics to advance edge caching capability, which is considered as a promising approach to improve network efficiency and alleviate the high demand for the radio resou…
A Double Auction Mechanism for Virtual Resource Allocation in SDN-based Cellular Network
2016
The explosively growing demands for mobile traffic service bring both challenges and opportunities to wireless net- works, among which, wireless network virtualization is proposed as the main evolution towards 5G. In this paper, we first propose a Software Defined Network (SDN) based wireless virtualization architecture for enabling multi-flow transmission in order to save capital expenses (CapEx) and operation expenses (OpEx) significantly with multiple Infrastructures Providers (InPs) and multiple Mobile Virtual Network Operators (MVNOs). We for- mulate the virtual resource allocation problem with diverse QoS requirements as a social welfare maximization problem with transaction cost. Due…
Energy Efficient Optimization for Wireless Virtualized Small Cell Networks With Large-Scale Multiple Antenna
2017
Wireless network virtualization is envisioned as a promising framework to provide efficient and customized services for next-generation wireless networks. In wireless virtualized networks (WVNs), limited radio resources are shared among different services providers for providing services to different users with heterogeneous demands. In this paper, we propose a resource allocation scheme for an orthogonal frequency division multiplexing-based WVN, where one small cell base station equipped with a large number of antennas serves the users with different service requirements. In particular, with the objective to obtain the energy efficiency in the uplink, a joint power, subcarrier, and antenn…
Service-Oriented Wireless Virtualized Networks: An Intelligent Resource Management Approach
2022
Trajectory Design and Resource Allocation for Multi-UAV Networks : Deep Reinforcement Learning Approaches
2023
The future mobile communication system is expected to provide ubiquitous connectivity and unprecedented services over billions of devices. The unmanned aerial vehicle (UAV), which is prominent in its flexibility and low cost, emerges as a significant network entity to realize such ambitious targets. In this work, novel machine learning-based trajectory design and resource allocation schemes are presented for a multi-UAV communications system. In the considered system, the UAVs act as aerial Base Stations (BSs) and provide ubiquitous coverage. In particular, with the objective to maximize the system utility over all served users, a joint user association, power allocation and trajectory desi…
Resource Allocation and Computation Offloading for Wireless Powered Mobile Edge Computing
2022
In this paper, we investigate a resource allocation and computation offloading problem in a heterogeneous mobile edge computing (MEC) system. In the considered system, a wireless power transfer (WPT) base station (BS) with an MEC sever is able to deliver wireless energy to the mobile devices (MDs), and the MDs can utilize the harvested energy for local computing or task offloading to the WPT BS or a Macro BS (MBS) with a stronger computing server. In particular, we consider that the WPT BS can utilize full- or half-duplex wireless energy transmission mode to empower the MDs. The aim of this work focuses on optimizing the offloading decision, full/half-duplex energy harvesting mode and energ…
The MIMOSE Approach to Support Sustainable Forest Management Planning at Regional Scale in Mediterranean Contexts
2017
In recent decades, Mediterranean landscapes have been affected by human-induced drivers, such as land use and climate change. Forest ecosystems and landscapes have been particularly affected in mountainous regions due to limited management and stewardship, especially in remote areas. Therefore, there is a need to set up new strategies to enhance ecosystem services in forested areas which, in turn, will benefit local communities and economies. In this study, we implemented a new approach—Multiscale Mapping of Ecosystem Services (MIMOSE)—to assess ecosystem services in Mediterranean forests located in a mountainous region of Italy. We spatially assessed timber provision and carbon sequestrati…
Assessment of Occupational Health and Job Satisfaction in Workers with Intellectual Disability: A Job Demands–Resources Perspective
2021
In the contexts where people with intellectual disability work, there are factors that determine their job satisfaction. The objective of this study was to test the adequacy of the central assumptions of the Job Demands–Resources (JD-R) theory in workers with intellectual disability employed in different work alternatives. Data from 362 workers in sheltered workshops and 192 workers in supported employment were utilized. The model was contrasted using a structural equation model and a multi-group analysis. The results supported the suitability of the model and confirmed that job demands and job resources evoke two relatively independent processes such as health impairment and motivational p…