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1.
This paper presents an extended, harmonised account of our previous work on combining subsentential alignments from phrase-based
statistical machine translation (SMT) and example-based MT (EBMT) systems to create novel hybrid data-driven systems capable
of outperforming the baseline SMT and EBMT systems from which they were derived. In previous work, we demonstrated that while
an EBMT system is capable of outperforming a phrase-based SMT (PBSMT) system constructed from freely available resources,
a hybrid ‘example-based’ SMT system incorporating marker chunks and SMT subsentential alignments is capable of outperforming
both baseline translation models for French–English translation. In this paper, we show that similar gains are to be had from
constructing a hybrid ‘statistical’ EBMT system. Unlike the previous research, here we use the Europarl training and test
sets, which are fast becoming the standard data in the field. On these data sets, while all hybrid ‘statistical’ EBMT variants
still fall short of the quality achieved by the baseline PBSMT system, we show that adding the marker chunks to create a hybrid
‘example-based’ SMT system outperforms the two baseline systems from which it is derived. Furthermore, we provide further
evidence in favour of hybrid systems by adding an SMT target-language model to the EBMT system, and demonstrate that this
too has a positive effect on translation quality. We also show that many of the subsentential alignments derived from the
Europarl corpus are created by either the PBSMT or the EBMT system, but not by both. In sum, therefore, despite the obvious
convergence of the two paradigms, the crucial differences between SMT and EBMT contribute positively to the overall translation
quality. The central thesis of this paper is that any researcher who continues to develop an MT system using either of these
approaches will benefit further from integrating the advantages of the other model; dogged adherence to one approach will
lead to inferior systems being developed. 相似文献
2.
Modeling and Control of Linear Two-time Scale Systems: Applied to Single-Link Flexible Manipulator 总被引:1,自引:0,他引:1
H. R. Karimi M. J. Yazdanpanah R. V. Patel K. Khorasani 《Journal of Intelligent and Robotic Systems》2006,45(3):235-265
This paper deals with the problem of H
∞ control of linear two-time scale systems. The authors’ attention is focused on the robust regulation of the system based on a new modeling approach under the assumption of norm-boundedness of the fast dynamics. In the proposed approach, the fast dynamics are treated as a norm-bounded disturbance (dynamic uncertainty). In this view, the synthesis is performed only for the certain dynamics of the two-time scale system, whose order is less than that of the original system. It should be noted, however, that this scheme is significantly different from the conventional approaches of order reduction for linear two-time scale systems. Specifically, in the present work, explicitly or implicitly, all the dynamics of the system are taken into consideration. In other words, the portion that is treated as a perturbation is incorporated in the design by its maximum possible gain – in the L
2 sense – over different values of the inputs. One of the advantagesof this approach is that – unlike in the conventional approaches of the order reduction – the reduced-order system still keeps some information of the ‘deleted’ subsystem. Also, we consider the robust stability analysis and stability bound improvement of perturbed parameter (ɛ) in the two-time scale systems by using linear fractional transformations and structured singular values (μ) approach. In this direction, by introducing the parametric uncertainty and dynamic uncertainty in the two-time scale systems, we represent the system as a standard μ-interconnection framework by using linear fractional transformations, and derive a set of new stability conditions for the system in the frequency domain. The exact solution of ɛ-bound is characterized. It is shown that, in spite of the coupling between the dynamic uncertainties and certain dynamics, the designed H
∞ controller stabilizes the overall closed-loop system, in the presence of norm-bounded disturbances. To show the effectiveness of the approach, the modeling of the single-link flexible manipulator and control of the Tip-position of the manipulator by utilizing the mentioned method are presented in the case study. 相似文献
3.
In the light of the developing discourse on the relative merits of ‘hard’ and ‘soft’ approaches to information systems development,
we present a case study application of a methodology which attempts to dissolve such dualities. Personal Construct Psychology
(PCP) offers, as a unity, the construing person who is both biology and culture. PCP argues that both the world and the person’s
construct system are phenomenologically real and that the viability of any particular construct system depends only on its
usefulness to the construing person. In this study, we used PCP to explore the organisational context of information use and
distribution in a large hospital. We used repertory grids, a PCP technique, to elicit from 16 members of staff their personal
construals of information from different sources in the hospital. The results highlight the relationship between meaningful
information and meaningfully active relationships, a theme which we discuss in terms of the development of the hospital information
system and in terms of the value of PCP in dissolving hard–soft dichotomies. 相似文献
4.
Stuart Jackson Nuala Brady Fred Cummins Kenneth Monaghan 《Artificial Intelligence Review》2006,26(1-2):141-154
Recent findings in neuroscience suggest an overlap between those brain regions involved in the control and execution of movement
and those activated during the perception of another’s movement. This so called ‘mirror neuron’ system is thought to underlie
our ability to automatically infer the goals and intentions of others by observing their actions. Kilner et al. (Curr Biol
13(6):522–525, 2003) provide evidence for a human ‘mirror neuron’ system by showing that the execution of simple arm movements
is affected by the simultaneous perception of another’s movement. Specifically, observation of ‘incongruent’ movements made
by another human, but not by a robotic arm, leads to greater variability in the movement trajectory than observation of movements
in the same direction. In this study we ask which aspects of the observed motion are crucial to this interference effect by
comparing the efficacy of real human movement to that of sparse ‘point-light displays’. Eight participants performed whole
arm movements in both horizontal and vertical directions while observing either the experimenter or a virtual ‘point-light’
figure making arm movements in the same or in a different direction. Our results, however, failed to show an effect of ‘congruency’
of the observed movement on movement variability, regardless of whether a human actor or point-light figure was observed.
The findings are discussed, and future directions for studies of perception-action coupling are considered. 相似文献
5.
Harry Buhrman Benjamin Hescott Steven Homer Leen Torenvliet 《Theory of Computing Systems》2010,47(2):317-341
We study properties of non-uniform reductions and related completeness notions. We strengthen several results of Hitchcock
and Pavan (ICALP (1), Lecture Notes in Computer Science, vol. 4051, pp. 465–476, Springer, 2006) and give a trade-off between the amount of advice needed for a reduction and its honesty on NEXP. We construct an oracle
relative to which this trade-off is optimal. We show, in a more systematic study of non-uniform reductions, among other things
that non-uniformity can be removed at the cost of more queries. In line with Post’s program for complexity theory (Buhrman
and Torenvliet in Bulletin of the EATCS 85, pp. 41–51, 2005) we connect such ‘uniformization’ properties to the separation of complexity classes. 相似文献
6.
This article offers a research update on a 3-year programme initiated by the Kamloops Art Gallery and the University College
of the Cariboo in Kamloops, British Columbia. The programme is supported by a ‘Community–University Research Alliance’ grant
from the Social Sciences and Humanities Research Council of Canada, and the collaboration focuses on the cultural future of
small cities – on how cultural and arts organisations work together (or fail to work together) in a small city setting. If
not by definition, then certainly by default, ‘culture’ is associated with big city life: big cities are equated commonly
with ‘big culture’; small cities with something less. The Cultural Future of Small Cities research group seeks to provide
a more nuanced view of what constitutes culture in a small Canadian city. In particular, the researchers are exploring notions
of social capital and community asset building: in this context, ‘visual and verbal representation’, ‘home’, ‘community’ and
the need to define a local ‘sense of place’ have emerged as important themes. As the Small Cities programme begins its second
year, a unique but key aspect has become the artist-as-researcher.
Correspondence and offprint requests to: L. Dubinsky, Kamloops Art Gallery, 101–465 Victoria Street, Kamloops, BC V2C 2A9 Canada. Tel.: 250-828-3543; Email: ldubinsky@museums.ca 相似文献
7.
Atsuyoshi Nakamura Jun-ichi Takeuchi Naoki Abe 《Annals of Mathematics and Artificial Intelligence》1998,23(1-2):53-82
We consider a variant of the ‘population learning model’ proposed by Kearns and Seung [8], in which the learner is required
to be ‘distribution-free’ as well as computationally efficient. A population learner receives as input hypotheses from a large
population of agents and produces as output its final hypothesis. Each agent is assumed to independently obtain labeled sample
for the target concept and output a hypothesis. A polynomial time population learner is said to PAC-learn a concept class,
if its hypothesis is probably approximately correct whenever the population size exceeds a certain bound which is polynomial,
even if the sample size for each agent is fixed at some constant. We exhibit some general population learning strategies,
and some simple concept classes that can be learned by them. These strategies include the ‘supremum hypothesis finder’, the
‘minimum superset finder’ (a special case of the ‘supremum hypothesis finder’), and various voting schemes. When coupled with
appropriate agent algorithms, these strategies can learn a variety of simple concept classes, such as the ‘high–low game’,
conjunctions, axis-parallel rectangles and others. We give upper bounds on the required population size for each of these
cases, and show that these systems can be used to obtain a speed up from the ordinary PAC-learning model [11], with appropriate
choices of sample and population sizes. With the population learner restricted to be a voting scheme, what we have is effectively
a model of ‘population prediction’, in which the learner is to predict the value of the target concept at an arbitrarily drawn
point, as a threshold function of the predictions made by its agents on the same point. We show that the population learning
model is strictly more powerful than the population prediction model. Finally, we consider a variant of this model with classification
noise, and exhibit a population learner for the class of conjunctions in this model.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
The notion of P-simple points was introduced by Bertrand to conceive parallel thinning algorithms. In ‘A 3D fully parallel thinning algorithm
for generating medial faces’ (Pattern Recogn. Lett. 16:83–87, 1995), Ma proposed an algorithm for which there are objects whose topology is not preserved. In this paper, we propose a new application
of P-simple points: to automatically correct Ma’s algorithm. 相似文献
9.
J. Rogalski 《Cognition, Technology & Work》1999,1(4):247-256
Managing dynamic environments often requires decision making under uncertainty and risk. Two types of uncertainty are involved:
uncertainty about the state and the evolution of the situation, and ‘openness’ of the possible actions to face possible consequences.
In an experimental study on risk management in dynamic situations, two contrasted ‘ecological’ scenarios – transposed from
effective situations of emergency management – were compared in order to identify the impact of their ‘openness’ in the subjects’
strategies for decision making. The ‘Lost Child’ scenario presented qualitative and irreversible consequences (child’s death)
and high uncertainty; it exerted high demands both in risk assessment (risk representation) and action elaboration and choice.
A less open situation (‘Hydrocarbon Fire’) required a main choice between two contrasted actions, with quantitative computable
consequences. The strategies of ‘experimental subjects’ (university students) and ‘operative subjects’ (professional fire-fighter
officers) were compared in order to evaluate the ecological validity of experimental research in this field, from the point
of view of the subjects themselves. The two scenarios appeared to be independent, so that quite different models of decision
making have to be hypothesised, differing by the importance of assessing risk and defining possible actions on the one hand,
and by the process of choice on the other. ‘Experimental’ subjects dramatically differed from ‘operative’ subjects when confronted
with the same scenario, particularly for the less technical but more demanding scenario. It is hypothesised that three components
might account for the effect of the situations and for the differences between and within groups of subjects: importance of
situation assessment, spatial abilities, and global orientation of activity in managing dynamic risk. 相似文献
10.
Pest Control Expert System for Tomato (PCEST) 总被引:4,自引:0,他引:4
This paper presents a real-life pest control expert system for tomato. The system involves two main subtasks, namely: ‘diagnose’
and ‘treat’. The ‘diagnose’ subtask finds out the causes of the growers' complaints, while the ‘treat’ subtask finds out a
treatment plan for these causes. CommonKADS methodology has been used to develop the system. Dependency network is used as
one of our knowledge representation schemes in both subtasks. An expert system evaluation methodology has been suggested and
applied to the developed system.
Received May 1998 / Revised January 1999 / Accepted in revised form May 1999 相似文献
11.
Andy Crabtree Steve Benford Mauricio Capra Martin Flintham Adam Drozd Nick Tandavanitj Matt Adams Ju Row Farr 《Computer Supported Cooperative Work (CSCW)》2007,16(1-2):167-198
This paper focuses on orchestration work in the first iteration of a mobile game called Day Of The Figurines, which explores the potential to exploit text messaging as a means of creating an engaging gaming experience. By focusing
on orchestration we are especially concerned with the ‘cooperative work that makes the game work’. While the assemblage or
family of orchestration practices uncovered by our ethnographic study are specific to the game – including the ways in which
behind the scenes staff make sense of messages, craft appropriate responses, and manage and track the production of gameplay
narratives as the game unfolds – orchestration work is of general significance to our understanding of new gaming experiences.
The focus on orchestration work reveals that behind the scenes staff are co-producers of the game and that the playing of games is, therefore, inseparably intertwined with their orchestration. Furthermore, orchestration
work is ‘ordinary’ work that relies upon the taken for granted skills and competences of behind the scenes staff; ‘operators’
and ‘authors’ in this case. While we remain focused on the specifics of this game, explication of the ordinary work of orchestration
highlights challenges and opportunities for the continued development of gaming experiences more generally. Indeed, understanding
the specificities of orchestration work might be said to be a key ingredient of future development. 相似文献
12.
David Martin Jacki O’neill Dave Randall Mark Rouncefield 《Computer Supported Cooperative Work (CSCW)》2007,16(3):231-264
As a comparatively novel but increasingly pervasive organizational arrangement, call centres have been a focus for much recent
research. This paper identifies lessons for organizational and technological design through an examination of call centres
and ‘classification work’ – explicating what Star [1992, Systems/Practice vol. 5, pp. 395–410] terms the ‘open black box’. Classification is a central means by which organizations standardize procedure,
assess productivity, develop services and re-organize their business. Nevertheless, as Bowker and Star [1999, Sorting Things Out: Classification and Its Consequences. Cambridge MA: MIT Press] have pointed out, we know relatively little about the work that goes into making classification
schema what they are. We will suggest that a focus on classification ‘work’ in this context is a useful exemplar of the need
for some kind of ‘meta-analysis’ in ethnographic work also. If standardization is a major ambition for organizations under
late capitalism, then comparison might be seen as a related but as-yet unrealized one for ethnographers. In this paper, we
attempt an initial cut at a comparative approach, focusing on classification because it seemed to be the primary issue that
emerged when we compared studies. Moreover, if technology is the principal means through which procedure and practice is implemented
and if, as we believe, classifications are becoming ever more explicitly embedded within it (for instance with the development
of so-called ‘semantic web’ and associated approaches to ontology-based design), then there is clearly a case for identifying
some themes which might underpin classification work in a given domain. 相似文献
13.
John Underkoffler 《Personal and Ubiquitous Computing》1997,1(1):28-40
Conclusion Four decades of sporadic invention and experimentation of and with non-traditional human-computer interface schemes have congealed
(somewhat abruptly though not without a few clear-sighted antecedents) into a new field of information system design, here
calledAntisedentary Beigeless Computing, that consciously rejects the traditional conception of isolated tete-a-tete between the human and the box-CRT-keyboardmouse.
ABC systems instead favour the complementary directions away from this notion of an immobile info-shrine: more personal, intimate,
and portable information access; and more diffuse, environmentally-integrated information access. Consideration of ABC projects
to date seems to suggest that no single instance can alone express the full generality required of a ‘working’ information
system, so that (on the one hand) system design must acknowledge that a complex set of trade-offs involving capabilities,
universality, specificity, personalization, and generality is inescapable; while (on the other hand) an ideal, eventual ‘information
environment’ will inevitably comprise the careful interweaving of some number of individual ABC systems.
Taxonomies and classification schema can rarely hope to be found complete or flawless before the collection of items that
they purport to describe have themselves reached the evolutionary stasis of ‘adulthood’ — that is, there is typically some
threshold of development or growth beyond which few enough surprises lurk that an encompassing taxonomy can be constructed
and observed to reliably encompass, in the longer term. The domain of ABC thought is still quite nascent, and so we would
be foolish to assume that all its extremities of form and connotation are now visible, but to the extent that we can already
see the outlines of a ‘field’ it is reasonable to make a first run at an analytic taxonomy. The ‘independent character axes’
approach presented here seems broad and loose enough to accommodate any number of additions to the basic stable of ABC systems.
It is, further, a taxonomy amenable to significant revision as may be found necessary: axes can be added, deleted, reconstrued,
etc. as time and consideration clarify our understanding of ABC. However, it should also be anticipated that the field will
eventually coalesce around a much smaller number of better-defined ‘axes’ and thus permit taxonomic reversion to the more
hierarchical (and finally more satisfying) ‘Linnean’ scheme we'd originally imagined establishing. 相似文献
14.
In this paper, we demonstrate how craft practice in contemporary jewellery opens up conceptions of ‘digital jewellery’ to
possibilities beyond merely embedding pre-existing behaviours of digital systems in objects, which follow shallow interpretations
of jewellery. We argue that a design approach that understands jewellery only in terms of location on the body is likely to
lead to a world of ‘gadgets’, rather than anything that deserves the moniker ‘jewellery’. In contrast, by adopting a craft
approach, we demonstrate that the space of digital jewellery can include objects where the digital functionality is integrated
as one facet of an object that can be personally meaningful for the holder or wearer. 相似文献
15.
DSM as a knowledge capture tool in CODE environment 总被引:1,自引:0,他引:1
A design structure matrix (DSM) provides a simple, compact, and visual representation of a complex system/ process. This paper
shows how DSM, a system engineering tool, is applied as a knowledge capture (acquisition) tool in a generic NPD process. The
acquired knowledge (identified in the DSM) is provided in the form of Questionnaires, which are organized into five performance
indicators of the organization namely ‘Marketing’, ‘Technical’, ‘Financial’, ‘Resource Management’, and ‘Project Management’.
Industrial application is carried out for knowledge validation. It is found form the application that the acquired knowledge
helps NPD teams, managers and stakeholders to benchmark their NPD endeavor and select areas to focus their improvement efforts
(up to 80% valid). 相似文献
16.
In this paper, we describe a formal framework for conformance testing of continuous and hybrid systems, using the international
standard ‘Formal Methods in Conformance Testing’ FMCT. We propose a novel test coverage measure for these systems, which is
defined using the star discrepancy notion. This coverage measure is used to quantify the validation ‘completeness’. It is
also used to guide input stimulus generation by identifying the portions of the system behaviors that are not adequately examined.
We then propose a test generation method, which is based on a robotic motion planning algorithm and is guided by the coverage
measure. This method was implemented in a prototype tool that can handle high dimensional systems (up to 100 dimensions). 相似文献
17.
Stability of solutions of delay functional integro-differential equations and their discretizations 总被引:2,自引:0,他引:2
In this paper we study asymptotic stability and contractivity properties of solutions of a class of delay functional integro-differential equations. These results form the basis for obtaining insight into the analogous properties of numerical solutions generated by continuous Runge-Kutta or collocation methods, where these methods are applied to a suitable reformulation of the given initial-value problem. 相似文献
18.
Remote sensing imaging techniques make use of data derived from high resolution satellite sensors. Image classification identifies
and organises pixels of similar spatial distribution or similar statistical characteristics into the same spectral class (theme).
Contextual data can be incorporated, or ‘fused’, with spectral data to improve the accuracy of classification algorithms.
In this paper we use Dempster–Shafer’s theory of evidence to achieve this data fusion. Incorporating a Knowledge Base of evidence
within the classification process represents a new direction for the development of reliable systems for image classification
and the interpretation of remotely sensed data. 相似文献
19.
In this paper we argue that substitution-based function allocation methods (such as MABA-MABA, or Men-Are-Better-At/Machines-Are-Better-At
lists) cannot provide progress on human–automation co-ordination. Quantitative ‘who does what’ allocation does not work because
the real effects of automation are qualitative: it transforms human practice and forces people to adapt their skills and routines.
Rather than re-inventing or refining substitution-based methods, we propose that the more pressing question on human–automation
co-ordination is ‘How do we make them get along together?’
Correspondence and offprint requests to: S. W. A. Dekker, Department of Mechanical Engineering, IKP, Link?ping Institute of Technology, SE - 581 83 Link?ping, Sweden.
Tel.: +46 13 281646; fax +4613282579; email: sidde@ikp.liu.se 相似文献
20.
Abstract
In this paper, we use the group inverse to characterize the quotient convergence of an iterative method for solving consistent
singular linear systems, when the matrix index equals one. Next, we show that for stationary splitting iterative methods,
the convergence and the quotient convergence are equivalent, which was first proved in [7]. Lastly, we propose a (multi-)splitting
iterative method A=F–G, where the splitting matrix F may be singular, endowed with group inverse, by using F
# as a solution tool for any iteration. In this direction, sufficient conditions for the quotient convergence of these methods
are given. Then, by using the equivalence between convergence and quotient convergence, the classical convergence of these
methods is proved. These latter results generalize Cao’s result, which was given for nonsingular splitting matrices F.
Keywords: Group inverse, singular linear equations, iterative method, P-regular splitting, Hermitian positive definite matrix, multi-splitting, quotient convergence
AMS Classification: 15A09, 65F35 相似文献