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1.
We prove that any subset of ℝ 2 parametrized by a C
1 periodic function and its derivative is the Euclidean invariant signature of a closed planar curve. This solves a problem
posed by Calabi et al. (Int. J. Comput. Vis. 26:107–135, 1998). Based on the proof of this result, we then develop some cautionary examples concerning the application of signature curves
for object recognition and symmetry detection as proposed by Calabi et al.
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2.
Scenarios have been shown to be very helpful in identifying and communicating requirements for computer-based systems (CBSs). However, they appear not to be applicable to the rest of the CBS development process. Making scenarios more useful for the entire software development lifecycle requires integrating scenarios to other representations used during CBS development. This integration is achieved with tracing technology. Having integrated scenarios into the entire software development lifecycle creates the necessity to maintain scenarios through the inevitable changes that they and other documents undergo and to subject them to configuration management. We have prototyped automated support for full-lifecycle scenario management and have applied it to some non-trivial systems.This paper is an amalgamation and extension of the conference papers numbered 8, 9, 10, and 11 in the bibliography of this paper. 相似文献
3.
There are only a few ethical regulations that deal explicitly with robots, in contrast to a vast number of regulations, which
may be applied. We will focus on ethical issues with regard to “responsibility and autonomous robots”, “machines as a replacement
for humans”, and “tele-presence”. Furthermore we will examine examples from special fields of application (medicine and healthcare,
armed forces, and entertainment). We do not claim to present a complete list of ethical issue nor of regulations in the field
of robotics, but we will demonstrate that there are legal challenges with regard to these issues.
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4.
We present a study of using camera-phones and visual-tags to access mobile services. Firstly, a user-experience study is described in which participants were both observed learning to interact with a prototype mobile service and interviewed
about their experiences. Secondly, a pointing-device task is presented in which quantitative data was gathered regarding the speed and accuracy with which participants aimed and clicked
on visual-tags using camera-phones. We found that participants’ attitudes to visual-tag-based applications were broadly positive,
although they had several important reservations about camera-phone technology more generally. Data from our pointing-device
task demonstrated that novice users were able to aim and click on visual-tags quickly (well under 3 s per pointing-device
trial on average) and accurately (almost all meeting our defined speed/accuracy tradeoff of 6% error-rate). Based on our findings,
design lessons for camera-phone and visual-tag applications are presented.
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5.
We continue the study of zero-automatic queues first introduced in Dao-Thi and Mairesse (Adv Appl Probab 39(2):429–461, 2007). These queues are characterized by a special buffering mechanism evolving like a random walk on some infinite group or monoid.
The simple M/M/1 queue and Gelenbe’s G-queue with positive and negative customers are the two simplest 0-automatic queues. All stable 0-automatic queues have an
explicit “multiplicative” stationary distribution and a Poisson departure process (Dao-Thi and Mairesse, Adv Appl Probab 39(2):429–461,
2007). In this paper, we introduce and study networks of 0-automatic queues. We consider two types of networks, with either a
Jackson-like or a Kelly-like routing mechanism. In both cases, and under the stability condition, we prove that the stationary
distribution of the buffer contents has a “product-form” and can be explicitly determined. Furthermore, the departure process
out of the network is Poisson.
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6.
Moving point object data can be analyzed through the discovery of patterns in trajectories. We consider the computational
efficiency of detecting four such spatio-temporal patterns, namely flock, leadership, convergence, and encounter, as defined
by Laube et al., Finding REMO—detecting relative motion patterns in geospatial lifelines, 201–214, ( 2004). These patterns are large enough subgroups of the moving point objects that exhibit similar movement in the sense of direction,
heading for the same location, and/or proximity. By the use of techniques from computational geometry, including approximation
algorithms, we improve the running time bounds of existing algorithms to detect these patterns.
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7.
We provide the complete record of methodology that let us evolve BrilliAnt, the winner of the Ant Wars contest. Ant Wars contestants are virtual ants collecting food on a grid board in the presence
of a competing ant. BrilliAnt has been evolved through a competitive one-population coevolution using genetic programming
and fitnessless selection. In this paper, we detail the evolutionary setup that lead to BrilliAnt’s emergence, assess its
direct and indirect human-competitiveness, and describe the behavioral patterns observed in its strategy.
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8.
This paper describes the simulated car racing competition that was arranged as part of the 2007 IEEE Congress on Evolutionary
Computation. Both the game that was used as the domain for the competition, the controllers submitted as entries to the competition
and its results are presented. With this paper, we hope to provide some insight into the efficacy of various computational
intelligence methods on a well-defined game task, as well as an example of one way of running a competition. In the process,
we provide a set of reference results for those who wish to use the simplerace game to benchmark their own algorithms. The paper is co-authored by the organizers and participants of the competition.
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9.
We couple pseudo-particle modeling (PPM, Ge and Li in Chem Eng Sci 58(8):1565–1585, 2003), a variant of hard-particle molecular dynamics, with standard soft-particle molecular dynamics (MD) to study an idealized
gas–liquid flow in nano-channels. The coupling helps to keep sharp contrast between gas and liquid behaviors and the simulations
conducted provide a reference frame for exploring more complex and realistic gas–liquid nano-flows. The qualitative nature
and general flow patterns of the flow under such extreme conditions are found to be consistent with its macro-scale counterpart.
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10.
In the last few years, intelligent secured multimedia services play a vital role along with ubiquitous home environment (Park
et al. in Lecture Notes in Computer Science, vol. 4097, pp. 660–670, [ 2006]; Lecture Notes in Computer Science, vol. 4159, pp. 893–901, [ 2006]; IEICE Trans. Inf. Syst. E89-D(12):2831–2837, [ 2006]; Lecture Notes in Artificial Intelligence, vol. 4252, pp. 777–784, [ 2006]; Lecture Notes in Artificial Intelligence, vol. 3801, pp. 313–320, [ 2005]). There are certain constrains and limitations in providing effective and efficient services in U-home. The mechanism and
applications are integrated to realize such services. Three different kinds of ubiquitous multimedia services are proposed
in the framework. Based on the temporal and spatial context information, the surrounding situations are recognized. The contexts
are collected and well analyzed with the preconditions to provide the final services. The proposed framework provides efficient
services in the multimedia based deices based on the current context information.
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11.
A number of mobile applications have emerged that allow users to locate one another. However, people have expressed concerns
about the privacy implications associated with this class of software, suggesting that broad adoption may only happen to the
extent that these concerns are adequately addressed. In this article, we report on our work on P eopleF inder, an application that enables cell phone and laptop users to selectively share their locations with others (e.g. friends,
family, and colleagues). The objective of our work has been to better understand people’s attitudes and behaviors towards
privacy as they interact with such an application, and to explore technologies that empower users to more effectively and
efficiently specify their privacy preferences (or “policies”). These technologies include user interfaces for specifying rules
and auditing disclosures, as well as machine learning techniques to refine user policies based on their feedback. We present
evaluations of these technologies in the context of one laboratory study and three field studies.
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12.
Some second order PDE-based image restoration models such as total variation (TV) minimization or ROF model of Rudin et al.
(Physica D 60, 259–268, 1992) can easily give rise to staircase effect, which may produce undesirable blocky image. LOT model proposed by Laysker, Osher
and Tai (IEEE Trans. Image Process. 13(10), 1345–1357, 2004) has alleviated the staircase effect successfully, but the algorithms are complicated due to three nonlinear second-order
PDEs to be computed, besides, when we have no information about the noise, the model cannot preserve edges or textures well.
In this paper, we propose an improved LOT model for image restoration. First, we smooth the angle θ rather than the unit normal vector n, where n=(cos θ,sin θ). Second, we add an edge indicator function in order to preserve fine structures such as edges and textures well. And then
the dual formulation of TV-norm and TV
g
-norm are used in the numerical algorithms. Finally, some numerical experiments prove our proposed model and algorithms to
be effective.
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13.
The recent paper by Wang et al. (J. Supercomput. 38:155–172, 2006) proposed a Hyper Erlang model for long-tailed network traffic approximation. The paper argued that traditional models such as the Pareto, Weibull and log
normal distributions are difficult to apply because of “their complex representations and theoretical properties”. The paper
went on to say that the Pareto distribution “does not have analytic Laplace transform, and many other heavy-tailed distributions,
such as Weibull and log normal also do not have closed-form Laplace transforms”.
In the following, we would like to show that one can actually derive explicit expressions for Laplace transforms of heavy-tailed
distributions. The next three sections provide explicit expressions for the Laplace transforms of the Pareto, Weibull and
the log-normal distributions. To the best of our knowledge, these are the first known results on Laplace transforms of heavy-tailed
distributions.
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14.
In the article a certain class of feature extractors for face recognition is presented. The extraction is based on simple
approaches: image scaling with pixel concatenation into a feature vector, selection of a small number of points from the face
area, face image’s spectrum, and finally pixel intensities histogram. The experiments performed on several facial image databases
(BioID [ 4], ORL face database [ 27], FERET [ 30]) show that face recognition using this class of extractors is particularly efficient and fast, and can have straightforward
implementations in software and hardware systems. They can also be used in fast face recognition system involving feature-integration,
as well as a tool for similar faces retrieval in 2-tier systems (as initial processing, before exact face recognition).
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15.
We further develop the mathematical theory of causal interventions, extending earlier results of Korb, Twardy, Handfield, & Oppy, ( 2005) and Spirtes, Glymour, Scheines ( 2000). Some of the skepticism surrounding causal discovery has concerned the fact that using only observational data can radically underdetermine the best explanatory causal model, with the true causal model appearing inferior to a simpler, faithful model (cf. Cartwright, ( 2001). Our results show that experimental data, together with some plausible assumptions, can reduce the space of viable explanatory causal models to one. 相似文献
16.
The purposes of this study are (a) to establish a measurement for evaluating conversational impressions of group discussions,
and (b) to make an exploratory investigation on their interactional processes which may affect to form those impressions.
The impression rating and factor analysis undertaken first give us four factors concerning conversational impressions of “focus
group interviews (FGIs)”: conversational activeness, conversational sequencing, the attitudes of participants and the relationships
of participants. In relation to the factors of conversational activeness and conversational sequencing in particular, the
microanalysis of four selected topical scenes from our database further shows that the behavior of the moderator and the interviewees
is organized not independently but with reference to each other. The study thus emphasizes the importance of the integration
of quantitative and qualitative approaches towards human interactions.
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17.
The likelihood theory of evidence (LTE) says, roughly, that all the information relevant to the bearing of data on hypotheses (or models) is contained in the likelihoods. There exist counterexamples in which one can tell which of two hypotheses is true from the full data, but not from the likelihoods alone. These examples suggest that some forms of scientific reasoning, such as the consilience of inductions (Whewell, 1858. In Novum organon renovatum (Part II of the 3rd ed.). The philosophy of the inductive sciences. London: Cass, 1967), cannot be represented within Bayesian and Likelihoodist philosophies of science. 相似文献
18.
I investigate the relationship between adaptation, as defined in evolutionary theory through natural selection, and the concept
of emergence. I argue that there is an essential correlation between the former, and “emergence” defined in the field of algorithmic
simulations. I first show that the computational concept of emergence (in terms of incompressible simulation) can be correlated
with a causal criterion of emergence (in terms of the specificity of the explanation of global patterns). On this ground,
I argue that emergence in general involves some sort of selective processes. Finally, I show that a second criterion, concerning
novel explanatory regularities following the emergence of a pattern, captures the robustness of emergence displayed by some
cases of emergence (according to the first criterion). Emergent processes fulfilling both criteria are therefore exemplified
in evolutionary biology by some so-called “innovations”, and mostly by the new units of fitness or new kinds of adaptations (like sexual reproduction, multicellular organisms, cells, societies) sometimes called “major transitions
in evolution”, that recent research programs (Maynard-Smith and Szathmary 1995; Michod 1999) aims at explaining.
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19.
This paper traces the history of policy-based management and how it evolved from the first security models dating back to
the late 1960’s until today’s more elaborate frameworks, languages, and policy-based management tools. The focus will be on
providing a synthesized chronicle of the evolution of ideas and research trends rather than on surveying the various specification
formalisms, frameworks, and application domains of policy-based management.
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20.
To get the maximum benefit from ambient intelligence (AmI), we need to anticipate and react to possible drawbacks and threats
emerging from the new technologies in order to devise appropriate safeguards. The SWAMI project took a precautionary approach
in its exploration of the privacy risks in AmI and sought ways to reduce them. It constructed four “dark scenarios” showing
possible negative implications of AmI, notably for privacy protection. Legal analysis of the depicted futures showed the shortcomings
of the current legal framework in being able to provide adequate privacy protection in the AmI environment. In this paper,
the authors, building upon their involvement in SWAMI research as well as the further advancement of EU privacy analysis,
identify various outstanding issues regarding the legal framework that still need to be resolved in order to deal with AmI
in an equitable and efficacious way. This article points out some of the lacunae in the legal framework and postulates several
privacy-specific safeguards aimed at overcoming them.
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