In this paper, a new methodology is presented for detecting anomalies from radiographic images. This methodology exploits a statistical model adapted to the content of radiographic images together with the hypothesis testing theory. The main contributions are the following. First, by using a generic model of radiographies based on the acquisition pipeline, the whole non-destructive testing proc...

This paper analyzes bottled water expenditures data with zero observations by employing parametric and semiparametric models. The overall results of specification tests indicate that the semiparametric model outperforms the parametric model significantly.  2000 Elsevier Science S.A. All rights reserved.

Suppose the random vector (X,Y ) satisfies the regression model Y = m(X) + σ(X)ε, where m(·) = E(Y |·), σ2(·) = Var(Y |·) and ε is independent of X. The covariate X is d-dimensional (d ≥ 1), the response Y is one-dimensional, and m and σ are unknown but smooth functions. In this paper we study goodness-of-fit tests for the parametric form of the error distribution under this model, without assu...

Efficient heavy haul operations require accurate predictions of terminal arrival times and equipment cycle times. Most analytical and parametric approaches for railway capacity evaluation and operations planning focus on predicting average train delay and not the performance of individual trains and their delay distribution. In practice, train delay varies about this average according to some d...

The solar system r-abundance distribution is commonly derived from the observed solar values by subtracting the possible nucleosynthetic contribution of the s-process. The new parametric model of the s-process called the canonical multievent model is used to derive the s-component of the solar abundance distribution and to study the impact of nuclear and observational uncertainties on the solar...

The question of having sufficient surveillance capability to detect illicit behaviour in order to inform decision makers in a timely fashion is of the ultimate importance to defence, security, law enforcement, and regulatory agencies. Quantifying such capability provides a means of informing asset allocation, as well as establishing the link to risk of mission failure. Individual sensor models ...

This paper presents a new model for trajectories in video sequences using mixtures of motion fields. Each field is described by a simple parametric model with only a few parameters. We show that, despite the simplicity of the motion fields, the overall model is able to generate complex trajectories occuring in video analysis.

We present an automatic method for computing an accurate parametric model of a piecewise defined pipe surface, consisting of cylinder and torus segments, from an unorganized point set. Our main contributions are reconstruction of the spine curve of a pipe surface from surface samples, and approximation of the spine curve by G1 continuous circular arcs and line segments. Our algorithm accurately...

We describe a program called SketchIT that transforms a single sketch of a mechanical device into multiple families of new designs. It represents each of these families with a “BEP-Model,” a parametric model augmented with constraints that ensure the device produces the desired behavior. The program is based on qualitative configuration space (qc-space), a novel representation that captures mec...