367 research outputs found
Efficient Cooperative Anycasting for AMI Mesh Networks
We have, in recent years, witnessed an increased interest towards enabling a
Smart Grid which will be a corner stone to build sustainable energy efficient
communities. An integral part of the future Smart Grid will be the
communications infrastructure which will make real time control of the grid
components possible. Automated Metering Infrastructure (AMI) is thought to be a
key enabler for monitoring and controlling the customer loads. %RPL is a
connectivity enabling mechanism for low power and lossy networks currently
being standardized by the IETF ROLL working group. RPL is deemed to be a
suitable candidate for AMI networks where the meters are connected to a
concentrator over multi hop low power and lossy links. This paper proposes an
efficient cooperative anycasting approach for wireless mesh networks with the
aim of achieving reduced traffic and increased utilisation of the network
resources. The proposed cooperative anycasting has been realised as an
enhancement on top of the Routing Protocol for Low Power and Lossy Networks
(RPL), a connectivity enabling mechanism in wireless AMI mesh networks. In this
protocol, smart meter nodes utilise an anycasting approach to facilitate
efficient transport of metering data to the concentrator node. Moreover, it
takes advantage of a distributed approach ensuring scalability
Isolating SDN Control Traffic with Layer-2 Slicing in 6TiSCH Industrial IoT Networks
Recent standardization efforts in IEEE 802.15.4-2015 Time Scheduled Channel
Hopping (TSCH) and the IETF 6TiSCH Working Group (WG), aim to provide
deterministic communications and efficient allocation of resources across
constrained Internet of Things (IoT) networks, particularly in Industrial IoT
(IIoT) scenarios. Within 6TiSCH, Software Defined Networking (SDN) has been
identified as means of providing centralized control in a number of key
situations. However, implementing a centralized SDN architecture in a Low Power
and Lossy Network (LLN) faces considerable challenges: not only is controller
traffic subject to jitter due to unreliable links and network contention, but
the overhead generated by SDN can severely affect the performance of other
traffic. This paper proposes using 6TiSCH tracks, a Layer-2 slicing mechanism
for creating dedicated forwarding paths across TSCH networks, in order to
isolate the SDN control overhead. Not only does this prevent control traffic
from affecting the performance of other data flows, but the properties of
6TiSCH tracks allows deterministic, low-latency SDN controller communication.
Using our own lightweight SDN implementation for Contiki OS, we firstly
demonstrate the effect of SDN control traffic on application data flows across
a 6TiSCH network. We then show that by slicing the network through the
allocation of dedicated resources along a SDN control path, tracks provide an
effective means of mitigating the cost of SDN control overhead in IEEE
802.15.4-2015 TSCH networks
Application of multiple-wireless to a visual localisation system for emergency services
AbstractâIn this paper we discuss the application of multiplewireless technology to a practical context-enhanced service system called ViewNet. ViewNet develops technologies to support enhanced coordination and cooperation between operation teams in the emergency services and the police. Distributed localisation of users and mapping of environments implemented over a secure wireless network enables teams of operatives to search and map an incident area rapidly and in full coordination with each other and with a control centre. Sensing is based on fusing absolute positioning systems (UWB and GPS) with relative localisation and mapping from on-body or handheld vision and inertial sensors. This paper focuses on the case for multiple-wireless capabilities in such a system and the benefits it can provide. We describe our work of developing a software API to support both WLAN and TETRA in ViewNet. It also provides a basis for incorporating future wireless technologies into ViewNet. I
Determinant of Stock Market Return Correlation: An Extented Gravity Model Approach
During the last several years a large number of studies have expressed increasing concerns regarding to importance of stock market correlation across the countries due to diversification problem. Most of the emprical studies try to measure correlation between stock market returns across countries without questioning that what drives correlation. The main objective of this study is to investigate the determinant of correlation between Istanbul Stock Exchange (ISE) return and stock market returns for selected countries over the 1991:1–2006:12 period by employing the extented gravity model with a panel regression econometric technique. This study departure from previous studies in two ways. First, study focuses on determinant of correlation between ISE return and selected 39 developed and developing countries from different regions. Second, two new variables (level of democracy and European Union (EU) membership) used to explain correlation between ISE return and return of selected countries stock market. Result from panel data regression showed that ISE is more correlated with democratic countries stock market. Also, if there is volatility in world stock markets return, correlation between ISE and selected stock market returns will increase
Smart Grid Communications: Overview of Research Challenges, Solutions, and Standardization Activities
Optimization of energy consumption in future intelligent energy networks (or
Smart Grids) will be based on grid-integrated near-real-time communications
between various grid elements in generation, transmission, distribution and
loads. This paper discusses some of the challenges and opportunities of
communications research in the areas of smart grid and smart metering. In
particular, we focus on some of the key communications challenges for realizing
interoperable and future-proof smart grid/metering networks, smart grid
security and privacy, and how some of the existing networking technologies can
be applied to energy management. Finally, we also discuss the coordinated
standardization efforts in Europe to harmonize communications standards and
protocols.Comment: To be published in IEEE Communications Surveys and Tutorial
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