130,967 research outputs found
Use of proofs-as-programs to build an anology-based functional program editor
This thesis presents a novel application of the technique known as proofs-as-programs.
Proofs-as-programs defines a correspondence between proofs in a constructive logic
and functional programs. By using this correspondence, a functional program may be
represented directly as the proof of a specification and so the program may be analysed within this proof framework. CʸNTHIA is a program editor for the functional
language ML which uses proofs-as-programs to analyse users' programs as they are
written. So that the user requires no knowledge of proof theory, the underlying proof
representation is completely hidden.
The proof framework allows programs written in CʸNTHIA to be checked to be
syntactically correct, well-typed, well-defined and terminating.
CʸNTHIA also embodies the idea of programming by analogy — rather than starting
from scratch, users always begin with an existing function definition. They then apply
a sequence of high-level editing commands which transform this starting definition into
the one required. These commands preserve correctness and also increase programming
efficiency by automating commonly occurring steps.
The design and implementation of CʸNTHIA is described and its role as a novice
programming environment is investigated. Use by experts is possible but only a sub-set of ML is currently supported. Two major trials of CʸNTHIA have shown that
CʸNTHIA is well-suited as a teaching tool. Users of CʸNTHIA make fewer programming errors and the feedback facilities of CʸNTHIA mean that it is easier to
track down the source of errors when they do occur
A logical foundation for session-based concurrent computation
Linear logic has long been heralded for its potential of providing a logical basis for concurrency.
While over the years many research attempts were made in this regard, a Curry-Howard correspondence between linear logic and concurrent computation was only found recently, bridging the proof theory of linear logic and session-typed process calculus. Building upon this work, we have
developed a theory of intuitionistic linear logic as a logical foundation for session-based concurrent computation, exploring several concurrency related phenomena such as value-dependent session
types and polymorphic sessions within our logical framework in an arguably clean and elegant way, establishing with relative ease strong typing guarantees due to the logical basis, which ensure the fundamental properties of type preservation and global progress, entailing the absence of deadlocks
in communication.
We develop a general purpose concurrent programming language based on the logical interpretation, combining functional programming with a concurrent, session-based process layer through the form of a contextual monad, preserving our strong typing guarantees of type preservation and
deadlock-freedom in the presence of general recursion and higher-order process communication.
We introduce a notion of linear logical relations for session typed concurrent processes, developing an arguably uniform technique for reasoning about sophisticated properties of session-based concurrent computation such as termination or equivalence based on our logical approach, further supporting our goal of establishing intuitionistic linear logic as a logical foundation for sessionbased concurrency
Genetic Programming for Smart Phone Personalisation
Personalisation in smart phones requires adaptability to dynamic context
based on user mobility, application usage and sensor inputs. Current
personalisation approaches, which rely on static logic that is developed a
priori, do not provide sufficient adaptability to dynamic and unexpected
context. This paper proposes genetic programming (GP), which can evolve program
logic in realtime, as an online learning method to deal with the highly dynamic
context in smart phone personalisation. We introduce the concept of
collaborative smart phone personalisation through the GP Island Model, in order
to exploit shared context among co-located phone users and reduce convergence
time. We implement these concepts on real smartphones to demonstrate the
capability of personalisation through GP and to explore the benefits of the
Island Model. Our empirical evaluations on two example applications confirm
that the Island Model can reduce convergence time by up to two-thirds over
standalone GP personalisation.Comment: 43 pages, 11 figure
An ontology framework for developing platform-independent knowledge-based engineering systems in the aerospace industry
This paper presents the development of a novel knowledge-based engineering (KBE) framework for implementing platform-independent knowledge-enabled product design systems within the aerospace industry. The aim of the KBE framework is to strengthen the structure, reuse and portability of knowledge consumed within KBE systems in view of supporting the cost-effective and long-term preservation of knowledge within such systems. The proposed KBE framework uses an ontology-based approach for semantic knowledge management and adopts a model-driven architecture style from the software engineering discipline. Its phases are mainly (1) Capture knowledge required for KBE system; (2) Ontology model construct of KBE system; (3) Platform-independent model (PIM) technology selection and implementation and (4) Integration of PIM KBE knowledge with computer-aided design system. A rigorous methodology is employed which is comprised of five qualitative phases namely, requirement analysis for the KBE framework, identifying software and ontological engineering elements, integration of both elements, proof of concept prototype demonstrator and finally experts validation. A case study investigating four primitive three-dimensional geometry shapes is used to quantify the applicability of the KBE framework in the aerospace industry. Additionally, experts within the aerospace and software engineering sector validated the strengths/benefits and limitations of the KBE framework. The major benefits of the developed approach are in the reduction of man-hours required for developing KBE systems within the aerospace industry and the maintainability and abstraction of the knowledge required for developing KBE systems. This approach strengthens knowledge reuse and eliminates platform-specific approaches to developing KBE systems ensuring the preservation of KBE knowledge for the long term
Towards an Abstract Domain for Resource Analysis of Logic Programs Using Sized Types
We present a novel general resource analysis for logic programs based on
sized types.Sized types are representations that incorporate structural (shape)
information and allow expressing both lower and upper bounds on the size of a
set of terms and their subterms at any position and depth. They also allow
relating the sizes of terms and subterms occurring at different argument
positions in logic predicates. Using these sized types, the resource analysis
can infer both lower and upper bounds on the resources used by all the
procedures in a program as functions on input term (and subterm) sizes,
overcoming limitations of existing analyses and enhancing their precision. Our
new resource analysis has been developed within the abstract interpretation
framework, as an extension of the sized types abstract domain, and has been
integrated into the Ciao preprocessor, CiaoPP. The abstract domain operations
are integrated with the setting up and solving of recurrence equations for
both, inferring size and resource usage functions. We show that the analysis is
an improvement over the previous resource analysis present in CiaoPP and
compares well in power to state of the art systems.Comment: Part of WLPE 2013 proceedings (arXiv:1308.2055
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