32,261 research outputs found
Design and application of a multi-modal process tomography system
This paper presents a design and application study of an integrated multi-modal system designed to support a range of common modalities: electrical resistance, electrical capacitance and ultrasonic tomography. Such a system is designed for use with complex processes that exhibit behaviour changes over time and space, and thus demand equally diverse sensing modalities. A multi-modal process tomography system able to exploit multiple sensor modes must permit the integration of their data, probably centred upon a composite process model. The paper presents an overview of this approach followed by an overview of the systems engineering and integrated design constraints. These include a range of hardware oriented challenges: the complexity and specificity of the front end electronics for each modality; the need for front end data pre-processing and packing; the need to integrate the data to facilitate data fusion; and finally the features to enable successful fusion and interpretation. A range of software aspects are also reviewed: the need to support differing front-end sensors for each modality in a generic fashion; the need to communicate with front end data pre-processing and packing systems; the need to integrate the data to allow data fusion; and finally to enable successful interpretation. The review of the system concepts is illustrated with an application to the study of a complex multi-component process
Current and Nascent SETI Instruments
Here we describe our ongoing efforts to develop high-performance and
sensitive instrumentation for use in the search for extra-terrestrial
intelligence (SETI). These efforts include our recently deployed Search for
Extraterrestrial Emissions from Nearby Developed Intelligent Populations
Spectrometer (SERENDIP V.v) and two instruments currently under development;
the Heterogeneous Radio SETI Spectrometer (HRSS) for SETI observations in the
radio spectrum and the Optical SETI Fast Photometer (OSFP) for SETI
observations in the optical band. We will discuss the basic SERENDIP V.v
instrument design and initial analysis methodology, along with instrument
architectures and observation strategies for OSFP and HRSS. In addition, we
will demonstrate how these instruments may be built using low-cost, modular
components and programmed and operated by students using common languages, e.g.
ANSI C.Comment: 12 pages, 5 figures, Original version appears as Chapter 2 in "The
Proceedings of SETI Sessions at the 2010 Astrobiology Science Conference:
Communication with Extraterrestrial Intelligence (CETI)," Douglas A. Vakoch,
Edito
Sonification of Network Traffic Flow for Monitoring and Situational Awareness
Maintaining situational awareness of what is happening within a network is
challenging, not least because the behaviour happens within computers and
communications networks, but also because data traffic speeds and volumes are
beyond human ability to process. Visualisation is widely used to present
information about the dynamics of network traffic dynamics. Although it
provides operators with an overall view and specific information about
particular traffic or attacks on the network, it often fails to represent the
events in an understandable way. Visualisations require visual attention and so
are not well suited to continuous monitoring scenarios in which network
administrators must carry out other tasks. Situational awareness is critical
and essential for decision-making in the domain of computer network monitoring
where it is vital to be able to identify and recognize network environment
behaviours.Here we present SoNSTAR (Sonification of Networks for SiTuational
AwaReness), a real-time sonification system to be used in the monitoring of
computer networks to support the situational awareness of network
administrators. SoNSTAR provides an auditory representation of all the TCP/IP
protocol traffic within a network based on the different traffic flows between
between network hosts. SoNSTAR raises situational awareness levels for computer
network defence by allowing operators to achieve better understanding and
performance while imposing less workload compared to visual techniques. SoNSTAR
identifies the features of network traffic flows by inspecting the status flags
of TCP/IP packet headers and mapping traffic events to recorded sounds to
generate a soundscape representing the real-time status of the network traffic
environment. Listening to the soundscape allows the administrator to recognise
anomalous behaviour quickly and without having to continuously watch a computer
screen.Comment: 17 pages, 7 figures plus supplemental material in Github repositor
An Overview on Application of Machine Learning Techniques in Optical Networks
Today's telecommunication networks have become sources of enormous amounts of
widely heterogeneous data. This information can be retrieved from network
traffic traces, network alarms, signal quality indicators, users' behavioral
data, etc. Advanced mathematical tools are required to extract meaningful
information from these data and take decisions pertaining to the proper
functioning of the networks from the network-generated data. Among these
mathematical tools, Machine Learning (ML) is regarded as one of the most
promising methodological approaches to perform network-data analysis and enable
automated network self-configuration and fault management. The adoption of ML
techniques in the field of optical communication networks is motivated by the
unprecedented growth of network complexity faced by optical networks in the
last few years. Such complexity increase is due to the introduction of a huge
number of adjustable and interdependent system parameters (e.g., routing
configurations, modulation format, symbol rate, coding schemes, etc.) that are
enabled by the usage of coherent transmission/reception technologies, advanced
digital signal processing and compensation of nonlinear effects in optical
fiber propagation. In this paper we provide an overview of the application of
ML to optical communications and networking. We classify and survey relevant
literature dealing with the topic, and we also provide an introductory tutorial
on ML for researchers and practitioners interested in this field. Although a
good number of research papers have recently appeared, the application of ML to
optical networks is still in its infancy: to stimulate further work in this
area, we conclude the paper proposing new possible research directions
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