552 research outputs found
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An investigation to study the feasibility of on-line bibliographic information retrieval system using an APP
This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University.This thesis reports an investigation on the feasibility study of a
searching mechanism using an APP suitable for an on-line bibliographic
retrieval, operation, especially for retrospective searches.
From the study of the searching methods used in the conventional
systems it is seen that elaborate file- and data- structures are
introduced to improve the response time of the system. These
consequently lead to software and hardware redundancies. To mask
these complexities of the system an expensive computer with higher
capabilities and more powerful instruction set is commonly used.
Thus the service of the systen becomes cost-ineffective.
On the other hand the primitive operations of a searching mechanism,
such as, association, domain selection, intersection and unions, are
the intrinsic features of an associative parallel processor. Therefore
it is important to establish the feasibility of an APP as a cost-effective
searching mechanise.
In this thesis a searching mechanism using an 'ON-THE-FLY' searching
technique has been proposed. The parallel search unit uses a Byte-oriented
VRL-APP for efficient character string processing.
At the time of undertaking this work the specification for neither the
retrieval systems nor the BO-VRL APP's were well established; hence a
two-phase investigation was originated. In the Phase I of the work a
bottom up approach was adopted to derive a formal and precise
specification for the BO-VRL-APP. During the Phase II of the work
a top-down approach was opted for the implementation of the searching
mechanism.
An experimental research vehicle has been developed to establish
the feasibility of an APP as a cost-effective searching mechanism.
Although rigorous proof of the feasibility has not been obtained,
the thesis establishes that the APP is well suited for on-line
bibligraphic information retrieval operations where substring searches
including boolean selection and threshold weights are efficiently
supported
From Verbs to Tasks: An Integrated Account of Learning Tasks from Situated Interactive Instruction.
Intelligent collaborative agents are becoming common in the human society. From virtual assistants such as Siri and Google Now to assistive robots, they contribute to human activities in a variety of ways. As they become more pervasive, the challenge of customizing them to a variety of environments and tasks becomes critical. It is infeasible for engineers to program them for each individual use. Our research aims at building interactive robots and agents that adapt to new environments autonomously by interacting with human users using natural modalities.
This dissertation studies the problem of learning novel tasks from human-agent dialog. We propose a novel approach for interactive task learning, situated interactive instruction (SII), and investigate approaches to three computational challenges that arise in designing SII agents: situated comprehension, mixed-initiative interaction, and interactive task learning. We propose a novel mixed-modality grounded representation for task verbs which encompasses their lexical, semantic, and
task-oriented aspects. This representation is useful in situated comprehension and can be learned through human-agent interactions. We introduce the Indexical Model of comprehension that can exploit
extra-linguistic contexts for resolving semantic ambiguities in situated comprehension of task commands. The Indexical model is integrated with a mixed-initiative interaction model that facilitates
a flexible task-oriented human-agent dialog. This dialog serves as the basis of interactive task learning. We propose an interactive variation of explanation-based learning that can acquire the proposed
representation. We demonstrate that our learning paradigm is efficient, can transfer knowledge between structurally similar tasks, integrates agent-driven exploration with instructional learning, and can acquire several tasks. The methods proposed in this thesis are integrated in Rosie - a generally instructable agent developed in the Soar cognitive architecture and embodied on a table-top robot.PhDComputer Science and EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111573/1/shiwali_1.pd
Design of testbed and emulation tools
The research summarized was concerned with the design of testbed and emulation tools suitable to assist in projecting, with reasonable accuracy, the expected performance of highly concurrent computing systems on large, complete applications. Such testbed and emulation tools are intended for the eventual use of those exploring new concurrent system architectures and organizations, either as users or as designers of such systems. While a range of alternatives was considered, a software based set of hierarchical tools was chosen to provide maximum flexibility, to ease in moving to new computers as technology improves and to take advantage of the inherent reliability and availability of commercially available computing systems
Perceptual Generalization and Context in a Network MemoryInspired Long-Term Memory for Artificial Cognition
Abstract: In the framework of open-ended learning cognitive architectures for robots, this paper deals with thedesign of a Long-Term Memory (LTM) structure that can accommodate the progressive acquisition ofexperience-based decision capabilities, or what different authors call “automation” of what is learnt, asa complementary system to more common prospective functions. The LTM proposed here provides fora relational storage of knowledge nuggets given the form of artificial neural networks (ANNs) that isrepresentative of the contexts in which they are relevant in a configural associative structure. It alsoaddresses the problem of continuous perceptual spaces and the task- and context-related generalizationor categorization of perceptions in an autonomous manner within the embodied sensorimotor apparatusof the robot. These issues are analyzed and a solution is proposed through the introduction of two newtypes of knowledge nuggets: P-nodes representing perceptual classes and C-nodes representing contexts.The approach is studied and its performance evaluated through its implementation and application to areal robotic experimentXunta de Galicia; ED431C 2017/12Xunta de Galicia; ED341D R2016/01
An analysis of the factors of conversion from a batch-processing, tape-oriented retrieval system to an on-line, real-time system
The factors for converting a batch-processing, tape-oriented document reference system to an-on-line, real-time system are discussed. The factors analyzed are file structures, file addressing, file maintenance, communication, scheduling, and modular programming structures. The levels of design for the individual factors are illustrated in order to show the complexities of conversion to an on-line, real-time system. It is concluded that system conversion from a batch-processing, tape-oriented system to an on-line, real-time system requires a total systems redesign, not a modification of the existing system. A vector model for system conversion is presented. The vector quantities of the model represent the factor levels and their probable costs-for implementation. It is concluded from the analysis and the vector model that interrelations between the factor levels must be followed for an operationally complete system conversion
ADAPTIVE MODEL BASED COMBUSTION PHASING CONTROL FOR MULTI FUEL SPARK IGNITION ENGINES
This research describes a physics-based control-oriented feed-forward model, combined with cylinder pressure feedback, to regulate combustion phasing in a spark-ignition engine operating on an unknown mix of fuels. This research may help enable internal combustion engines that are capable of on-the-fly adaptation to a wide range of fuels. These engines could; (1) facilitate a reduction in bio-fuel processing, (2) encourage locally-appropriate bio-fuels to reduce transportation, (3) allow new fuel formulations to enter the market with minimal infrastructure, and (4) enable engine adaptation to pump-to-pump fuel variations. These outcomes will help make bio-fuels cost-competitive with other transportation fuels, lessen dependence on traditional sources of energy, and reduce greenhouse gas emissions from automobiles; all of which are pivotal societal issues. Spark-ignition engines are equipped with a large number of control actuators to satisfy fuel economy targets and maintain regulated emissions compliance. The increased control flexibility also allows for adaptability to a wide range of fuel compositions, while maintaining efficient operation when input fuel is altered. Ignition timing control is of particular interest because it is the last control parameter prior to the combustion event, and significantly influences engine efficiency and emissions. Although Map-based ignition timing control and calibration routines are state of art, they become cumbersome when the number of control degrees of freedom increases are used in the engine. The increased system complexity motivates the use of model-based methods to minimize product development time and ensure calibration flexibility when the engine is altered during the design process. A closed loop model based ignition timing control algorithm is formulated with: 1) a feed forward fuel type sensitive combustion model to predict combustion duration from spark to 50% mass burned; 2) two virtual fuel property observers for octane number and laminar flame speed feedback; 3) an adaptive combustion phasing target model that is able to self-calibrate for wide range of fuel sources input. The proposed closed loop algorithm is experimentally validated in real time on the dynamometer. Satisfactory results are observed and conclusions are made that the closed loop approach is able to regulate combustion phasing for multi fuel adaptive SI engines
Solution of partial differential equations on vector and parallel computers
The present status of numerical methods for partial differential equations on vector and parallel computers was reviewed. The relevant aspects of these computers are discussed and a brief review of their development is included, with particular attention paid to those characteristics that influence algorithm selection. Both direct and iterative methods are given for elliptic equations as well as explicit and implicit methods for initial boundary value problems. The intent is to point out attractive methods as well as areas where this class of computer architecture cannot be fully utilized because of either hardware restrictions or the lack of adequate algorithms. Application areas utilizing these computers are briefly discussed
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Proceedings of ECAI International Workshop on Neural-Symbolic Learning and reasoning NeSy 2006
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