Shift and share projection models: A reformulation

Conclusions Tests of the simple projection models conducted in this study showed that a naive shift and share employment projection was superior to a model (Regional Rate) that depended only upon historical regional growth rates. The data confirmed, however, that there is enough instability in the regional share component to make a shift and share projection based upon a simple extrapolation of the component somewhat inferior to models (Ingrow and Super Ingrow) that utilize national historical and projected industry growth rates and omit any form of regional industry growth rate adjustment.The slight inferiority of the simple shift and share model tested does not mean that the technique holds no promise as a projection tool, but rather that the assumption of absolute stability of the regional share component over time requires modification. Even the very simple modification allowing for some convergence in regional industry growth rates (Modified Shift and Share) improved its predictive value to the point of superiority over the Ingrow model and to near equality with the Super Ingrow model. Further modification to substitute a multiplier projection assumption in local service industries and to take in account an inability to adequately project the regional share component for certain industries by setting the component equal to zero (Super Shift and Share) produced a model that was clearly superior.     

Quantifying motion in video recordings of neonatal seizures by robust motion trackers based on block motion models

This paper introduces a methodology for the development of robust motion trackers for video based on block motion models. According to this methodology, the motion of a site between two successive frames is estimated by minimizing an error function defined in terms of the intensities at these frames. The proposed methodology is used to develop robust motion trackers that rely on fractional block motion models. The motion trackers developed in this paper are utilized to extract motor activity signals from video recordings of neonatal seizures. The experimental results reveal that the proposed motion trackers are more accurate and reliable than existing motion tracking methods relying on pure translation and affine block motion models.     

Improving the accuracy and reliability of motion tracking methods used for extracting temporal motor activity signals from video recordings of neonatal seizures

This paper presents an approach for improving the accuracy and reliability of motion tracking methods developed for video based on block motion models. This approach estimates the displacement of a block of pixels between two successive frames by minimizing an error function defined in terms of the pixel intensities at these frames. The minimization problem is made analytically tractable by approximating the error function using a second-order Taylor expansion. The improved reliability of the proposed method is illustrated by its application in the extraction of temporal motor activity signals from video recordings of neonatal seizures.     

A function for generating nearly balanced binary search trees from sets of non-random keys

A function for generating nearly balanced binary search trees from sets of non-random keys is described. This function can be used in hashing organization where collisions are resolved by construction of binary trees. In particular it can be used as the secondary function in the relatively new technique of dynamic hashing.     

Wind velocity directional fluctuation prediction model

A two-dimensional analytical model of wind directional fluctuation exceedence rates is presented. The model assumes that wind directional fluctuations are binormally distributed. The model correctly predicts the trends but tends to underestimate the exceedence rates. Improvements by making the model three-dimensional are outlined.     

An evaluation of seasat SAR imagery for urban analysis

Digitally processed Seasat SAR imagery of the Denver, Colorado, area is analyzed with regard to the types of urban data that can be detected and/or inferred from satellite-borne L-band systems. Black-and-white images of the scene were generated at three scales to determine the advantages and detail discernible at each level of display. The large-scale imagery was density-sliced to evaluate the feasibility of producing a semiautomated land-cover classification from the SAR data. Gray level classes were assigned colors to aid interpretation and subsequently compared with the black-and-white images to assess the contribution of each technique and benefits of combining the data from both procedures.     

Reorientation effects in vitreous carbon and pyrolytic graphite

Tubular specimens of vitreous carbon and of pyrolytic graphite, heated in nitrogen or helium for several minutes at 2850 to 3100° K by RF induction, developed a skin of crystalline carbon, nodular in appearance and apparently growing into the carbon from the surface. The vitreous carbon was isotropic, with no preferred orientation of crystallites; the pyrolytic graphite had a preferred orientation of basal planes at right angles to the axis of the specimen, so that curved surfaces were composed predominantly of edge atoms. X-ray diffraction studies of the skin indicated that it was partially graphitised and strongly orientated with basal planes parallel to the surface. The mechanism of the reorientation process is as yet not clear, but the driving force may be a change in surface free energy.     

Triaxial Vector Accelerometry: A Method for Quantifying Tremor and Ataxia

A triaxial vector accelerometry system for quantitatively assessing tremor and ataxia is described. Since movement at a specific anatomical site can be three dimensional, previously reported single-and dual-axis methods are not satisfactory for quantitative analysis. The accelerometer contains three identical piezoelectric transducers, and it easily attaches to the wrist, hand, ankle, foot, etc., while the subject performs controlled repetitive movement of a particular anatomical site. Signals from the accelerometer are processed by associated electronic circuitry which provides a graphic write-out of selected parameters. Equations from which these parameters were derived are discussed, as is their integration into performance indexes. A brief report is given on testing of normal volunteers and patients presenting abnormal neuromuscular function.