The Aerospace Research Laboratory at the University of Virginia currently uses Particle Image Velocimetry (PIV) to measure the velocity fields of flow through a Mach 2 Scramjet Test Section. PIV is the method of tracking seed particles as they are carried through the flow, and using their velocities to create a velocity field. This method is limited by seed particles coating the windows, known ...

This paper presents fast recursive or moving windows algorithms for calculating local means in a diamond, hexagon and general polygonal shaped windows of an image. The algorithms for diamond shaped window require only seven or eight additions and subtractions per pixel. A number of other shapes of diamond windows such as skewed or parallelogram shaped diamond, long diamond, and lozenged diamond...

This paper describes a quantitative indicator for segmenting narrative text into coherent scenes. The indicator, called the lexical cohesion pro le (LCP), records lexical cohesiveness of words in a xed-length window moving word by word on the text. The cohesiveness of words, which represents their coherence, is computed by spreading activation on a semantic network. The basic idea of LCP is: (1...

Local adaptive lters for image restoration (denoising and deblurring), enhancement and target location local are described. The lters work in the domain of an orthogonal transform (DFT, DCT or other transforms) in a moving window and nonlinearly modify the transform coeecients to obtain an estimate of the central pixel of the window. A framework for the lter design for multi component images is...

One Sentence: This paper presents a novel method for window detection from mobile LiDAR data. Abstract: Mobile LiDAR (Light Detection And Ranging) data collection is a rapidly emerging technology in which multiple georeferenced sensors (e.g., laser scanners, cameras) are mounted on a moving vehicle to collect real world data. The photorealistic modeling of large-scale real world scenes such as ...

This paper presents the design and fabrication of an optical window for an optical modulator toward image sensing applications. An optical window consists of micrometer-order SiO2 capillaries (porous solid) that can modulate transmission light intensity by moving the liquid in and out of porous solid. A high optical transmittance of the optical window can be achieved due to refractive index mat...

Detection of natural selection operating at the amino acid sequence level is important in the study of molecular evolution. Single-site analysis and one-dimensional window analysis can be used to detect selection when the biological functions of amino acid sites are unknown. Single-site analysis is useful when selection operates more or less constantly over evolutionary time, but less so when s...

Using multi-scale ideas from wavelet analysis, we extend singular-spectrum analysis (SSA) to the study of nonstationary time series of length N whose intermittency can give rise to the divergence of their variance. The wavelet transform is a kind of local Fourier transform within a finite moving window whose width W , proportional to the major period of interest, is varied to explore a broad ra...

Measurements were made of the contrast required to see the direction of motion of drifting gratings (Part 1) and of moving bars (Part 2). The spatial frequency at which least contrast is required to see sinusoidal gratings decreases as their velocity increases, but peak sensitivity is identical at all velocities up to 800 deg/sec. Similarly, the wider a single bar, the higher the velocity at wh...

There have been many studies on management of moving objects recently. Most of them try to optimize the performance of predictive window queries. However, not much attention is paid to two other important query types: the predictive range query and the predictive k nearest neighbor query. In this article, we focus on these two types of queries. The novelty of our work mainly lies in the introdu...