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Working notes of the 1991 spring symposium on constraint-based reasoning
The exploitation of parallelism on shared memory multiprocessors
PhD ThesisWith the arrival of many general purpose shared memory multiple processor
(multiprocessor) computers into the commercial arena during the mid-1980's, a
rift has opened between the raw processing power offered by the emerging
hardware and the relative inability of its operating software to effectively deliver
this power to potential users. This rift stems from the fact that, currently, no
computational model with the capability to elegantly express parallel activity is
mature enough to be universally accepted, and used as the basis for programming
languages to exploit the parallelism that multiprocessors offer. To add to this,
there is a lack of software tools to assist programmers in the processes of designing
and debugging parallel programs.
Although much research has been done in the field of programming languages,
no undisputed candidate for the most appropriate language for programming
shared memory multiprocessors has yet been found. This thesis examines why this
state of affairs has arisen and proposes programming language constructs,
together with a programming methodology and environment, to close the ever
widening hardware to software gap.
The novel programming constructs described in this thesis are intended for use
in imperative languages even though they make use of the synchronisation
inherent in the dataflow model by using the semantics of single assignment when
operating on shared data, so giving rise to the term shared values. As there are
several distinct parallel programming paradigms, matching flavours of shared
value are developed to permit the concise expression of these paradigms.The Science and Engineering Research Council
Declarative domain-specific languages and applications to network monitoring
Os Sistemas de Detecção de Intrusões em Redes de Computadores são provavelmente
usados desde que existem redes de computadores. Estes sistemas têm como objectivo
monitorizarem o tráfego de rede, procurando anomalias, comportamentos indesejáveis
ou vestígios de ataques conhecidos, por forma a manter utilizadores, dados, máquinas
e serviços seguros, garantindo que as redes de computadores são locais de trabalho
seguros.
Neste trabalho foi desenvolvido um Sistema de Detecção de Intrusões em Redes de
Computadores, chamado NeMODe (NEtwork MOnitoring DEclarative approach), que
fornece mecanismos de detecção baseados em Programação por Restrições, bem como
uma Linguagem Específica de Domínio criada para modelar ataques específicos, usando
para isso metodologias de programação declarativa, permitindo relacionar vários
pacotes de rede e procurar intrusões que se propagam por vários pacotes e ao longo do
tempo.
As principais contribuições do trabalho descrito nesta tese são:
Uma abordagem declarativa aos Sistema de Detecção de Intrusões em Redes
de Computadores, incluindo mecanismos de detecção baseados em Programação
por Restrições, permitindo a detecção de ataques distribuídos ao longo de vários
pacotes e num intervalo de tempo.
Uma Linguagem Específica de Domínio baseada nos conceitos de Programação
por Restrições, usada para descrever os ataques nos quais estamos interessados
em detectar.
Um compilador para a Linguagem Específica de Domínio fornecida pelo sistema
NeMODe, capaz de gerar múltiplos detectores de ataques baseados em Gecode,
Adaptive Search e MiniSat; ### Abstract:
Network Intrusion Detection Systems (NIDSs) are in use probably ever since there
are computer networks, with the purpose of monitoring network traffic looking for
anomalies, undesired behaviors or a trace of known intrusions to keep both users, data,
hosts and services safe, ensuring computer networks are a secure place to work.
In this work, we developed a Network Intrusion Detection System (NIDS) called
NeMODe (NEtwork MOnitoring DEclarative approach), which provides a detection
mechanism based on Constraint Programming (CP) together with a Domain Specific
Language (DSL) crafted to model the specific intrusions using declarative methodologies,
able to relate several network packets and look for intrusions which span several
network packets.
The main contributions of the work described in this thesis are:
A declarative approach to Network Intrusion Detection Systems, including detection
mechanisms based on several Constraint Programming approaches, allowing
the detection of network intrusions which span several network packets and spread
over time.
A Domain Specific Language (DSL) based on Constraint Programming methodologies,
used to describe the network intrusions which we are interested in finding
on the network traffic.
A compiler for the DSL able to generate multiple detection mechanisms based on
Gecode, Adaptive Search and MiniSat
Proceedings of the GPEA Polytechnic Summit 2022: Session Papers
Welcome to GPEA PS 2022
Each year the Polytechnic Summit assembles leaders, influencers and contributors who shape the future of polytechnic education. The Polytechnic Summit provides a forum to enable opportunities for collaboration and partnerships and for participants to focus on innovation in curriculum and pedagogy, to share best practices in active and applied learning, and discuss practice-based research to enhance student learning.
This year a view on the aspects of applied research will be added. How to conduct research in a teaching first environment and make use of this. Which characteristics of applied research are important to be used in teaching and vice versa?The Summit will – once again - also provide an opportunity to examine the challenges and opportunities presented by COVID-19 and will offer us all an opportunity to explore the ways in which we can collaborate more effectively using our new-found virtual engagement skills and prepare for a hybrid future.
PS2022 Themes: Design (Programmes, Curriculum, Organisation);Practice-Based Learning;Applied Research; Employability and Graduate Skills; Internationalisation, Global Teaching & Collaboration and Sustainability Theme
Third Conference on Artificial Intelligence for Space Applications, part 1
The application of artificial intelligence to spacecraft and aerospace systems is discussed. Expert systems, robotics, space station automation, fault diagnostics, parallel processing, knowledge representation, scheduling, man-machine interfaces and neural nets are among the topics discussed
Fast Fourier transforms on energy-efficient application-specific processors
Many of the current applications used in battery powered devices are from digital signal processing, telecommunication, and multimedia domains. Traditionally application-specific fixed-function circuits have been used in these designs in form of application-specific integrated circuits (ASIC) to reach the required performance and energy-efficiency. The complexity of these applications has increased over the years, thus the design complexity has increased even faster, which implies increased design time. At the same time, there are more and more standards to be supported, thus using optimised fixed-function implementations for all the functions in all the standards is impractical. The non-recurring engineering costs for integrated circuits have also increased significantly, so manufacturers can only afford fewer chip iterations. Although tailoring the circuit for a specific application provides the best performance and/or energy-efficiency, such approach lacks flexibility. E.g., if an error is found after the manufacturing, an expensive chip iteration is required. In addition, new functionalities cannot be added afterwards to support evolution of standards.
Flexibility can be obtained with software based implementation technologies. Unfortunately, general-purpose processors do not provide the energy-efficiency of the fixed-function circuit designs. A useful trade-off between flexibility and performance is implementation based on application-specific processors (ASP) where programmability provides the flexibility and computational resources customised for the given application provide the performance.
In this Thesis, application-specific processors are considered by using fast Fourier transform as the representative algorithm. The architectural template used here is transport triggered architecture (TTA) which resembles very long instruction word machines but the operand execution resembles data flow machines rather than traditional operand triggering. The developed TTA processors exploit inherent parallelism of the application. In addition, several characteristics of the application have been identified and those are exploited by developing customised functional units for speeding up the execution. Several customisations are proposed for the data path of the processor but it is also important to match the memory bandwidth to the computation speed. This calls for a memory organisation supporting parallel memory accesses. The proposed optimisations have been used to improve the energy-efficiency of the processor and experiments show that a programmable solution can have energy-efficiency comparable to fixed-function ASIC designs
Advances in Character Recognition
This book presents advances in character recognition, and it consists of 12 chapters that cover wide range of topics on different aspects of character recognition. Hopefully, this book will serve as a reference source for academic research, for professionals working in the character recognition field and for all interested in the subject
Esprit '91. Proceedings of the annual Esprit conference. Brussels, 25-29 November 1991. EUR 13853 EN
SLEMS : a knowledge based approach to soil loss estimation and modelling
ThesisThesis (M.Sc.E.), University of New Brunswick, 199