Search results for "Wire"
showing 10 items of 1383 documents
A low power protocol to broadcast real-time data traffic in a clustered ad hoc network
2002
Energy saving is an extremely important design criteria for mobile ad hoc networks. We present the intra-cluster data-dissemination protocol (Icdp). The Icdp is used to group nodes around a special one, called the cluster leader (CL). The CL centralizes the power management mechanism and acts as a proxy for data transfer between the cluster and the rest of the nodes in the region. When a cluster node enables the power management it goes into "sleep" mode, to minimize power consumption. The CL buffers data frames for power saving stations and delivers them on the stations' request. We periodically distribute the cluster leader role among all the nodes inside the cluster, to not overload a si…
Strategies and Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer
2019
The continuous development of internet of things (IoT) infrastructure and applications is paving the way for advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Nodes (WSNs) able to collect and transmit data through wireless communication channels, while often positioned in locations that are difficult to access, is driving research into innovative solutions involving energy harvesting (EH) and wireless power transfer (WPT) to eventually allow battery-free sensor nodes. Due to the pervasiveness of radio frequency (RF) energy, RF EH and WPT are key technologies with the potential to power …
Zinc Oxide Nanowires on Printed Circuit Boards
2015
Printed circuit boards (PCBs), which are widely used for the fabrication of electronic circuits, can only withstand rather low temperatures. For this reason, the fabrication of high-density, long ZnO nanostructures on PCBs still remains a complex task. In fact, in absence of a seed-layer, whose annealing would require high temperatures, solution-growth methods only allow to synthesize low-density arrays of nanowires. Here we evaluate methods for overcoming this issue and, as a prototype, demonstrate a simple displacement sensor.
A Low-level Simulation Study of Prioritization in IEEE 802.11e Contention-based Networks
2006
This work deals with the performance evaluation of the IEEE 802.11e EDCA proposal for service prioritization in Wireless LANs. A large amount of study has been carried out in the scientific community to evaluate the performance of the EDCA proposal, mainly in terms of throughput and access delay differentiation. However, we argue that further performance insights are needed in order to fully understand the principles behind the EDCA prioritization mechanisms. To this purpose, rather than limit our investigation on throughput and delay performance figures, we take a closer look to their operation also in terms of low-level performance metrics (such as probability of accessing specific channe…
Design of Low-Cost Noise Measurement Sensor Network: Sensor Function Design
2010
In this paper, we report the sensor function design and implementation of a wireless sensor network application for measuring environmental acoustic noise. The system is built on ATmega128 and CC2420 platform. The protocol stack is based on CiNet stack with a global synchronization scheme and supports multi-hop communications. Strict filtering function specified by ITU-R 468 (namely A-weighting) is followed. Both the indoor and outdoor test results were compared with standard sound level meters (CESVA SC-20c and Pulsar94) and showed a less than ±2dB error in both short-term and longterm measurement. Power consumption has been measured that a single AA-type battery can sustain the applicatio…
From vertical to horizontal architecture
2006
Some of the main challenges related to wireless sensor networks implementation are low-quality communication, energy conservation, resource-constrained computation, distributed network management, data processing and the scalability of the protocols. This combination makes the implementation of software a demanding task and encourages to new approaches when thinking of software architecture.In this paper an architecture combining a low protocol stack with a cross-layer management entity is presented. One of the main ideas behind the architecture presented is to make application programming easier and to simplify the protocol stack in such a way that it would suit better for the limited reso…
Research Direction for Developing an Infrastructure for Mobile & Wireless Systems: Consensus Report of the NSF Workshop Held on October 15, 2001 …
2002
The recent NSF Workshop on Infrastructure for Mobile and Wireless Systems, held on Oct. 15, 2001 in Phoenix had a goal of defining and establishing a common infrastructure for the discipline of mobile wireless networking. This consensus-based paper is the outcome of that workshop. The paper provides a foundation for implementation, standardization, and further research and discussion on the issues of what should constitute such an infrastructure. Workshop participants came from many different wireless communities, including those of communications, operating systems, core networking, mobility, databases, and middleware. The workshop presented various research directions in the field and inc…
A Context-Aware System for Ambient Assisted Living
2017
In the near future, the world's population will be characterized by an increasing average age, and consequently, the number of people requiring for a special household assistance will dramatically rise. In this scenario, smart homes will significantly help users to increase their quality of life, while maintaining a great level of autonomy. This paper presents a system for Ambient Assisted Living (AAL) capable of understanding context and user's behavior by exploiting data gathered by a pervasive sensor network. The knowledge inferred by adopting a Bayesian knowledge extraction approach is exploited to disambiguate the collected observations, making the AAL system able to detect and predict…
AN INNOVATIVE SYSTEM FOR VINEYARD MANAGEMENT IN SICILY
2010
The aim of this study was to monitor the micro-climate of the grapevine in order to detect the adversities of the spring period (especially April and May), while reducing the operating costs of the vineyard, and increasing the overall quality of grapes. For this purpose a Wireless Sensor Network (WSN) was used. Furthermore, a comparison was performed between data measured by the wireless sensors and data provided by the fixed meteorological station of the Regione Siciliana (SIAS).
Energy-Efficiency and Coverage Quality Management for Reliable Diagnostics in Wireless Sensor Networks
2020
International audience; The processing of data and signals provided by sensors aims at extracting rnrelevant features which can be used to assess and diagnose the health state rnof the monitored targets. Nevertheless, Wireless Sensor Networks (WSNs) present rna number of shortcomings that have an impact on the quality of the gathered rndata at the sink level, leading to imprecise diagnostics rnof the observed targets. To improve data accuracy, two main critical and related issues, namely the energy consumption and coverage quality, need to be considered. The goal is to maximize the network lifetime while guaranteeing the complete coverage of all the targets. Unfortunately, these performance…