Object recognition using shape-from-shading

This paper investigates whether surface topography information extracted from intensity images using a recently reported shape-from-shading (SFS) algorithm can be used for the purposes of 3D object recognition. We consider how curvature and shape-index information delivered by this algorithm can be used to recognize objects based on their surface topography. We explore two contrasting object recognition strategies. The first of these is based on a low-level attribute summary and uses histograms of curvature and orientation measurements. The second approach is based on the structural arrangement of constant shape-index maximal patches and their associated region attributes. We show that region curvedness and a string ordering of the regions according to size provides recognition accuracy of about 96 percent. By polling various recognition schemes. including a graph matching method. we show that a recognition rate of 98-99 percent is achievable

New constraints on data-closeness and needle map consistency for shape-from-shading

This paper makes two contributions to the problem of needle-map recovery using shape-from-shading. First, we provide a geometric update procedure which allows the image irradiance equation to be satisfied as a hard constraint. This not only improves the data closeness of the recovered needle-map, but also removes the necessity for extensive parameter tuning. Second, we exploit the improved ease of control of the new shape-from-shading process to investigate various types of needle-map consistency constraint. The first set of constraints are based on needle-map smoothness. The second avenue of investigation is to use curvature information to impose topographic constraints. Third, we explore ways in which the needle-map is recovered so as to be consistent with the image gradient field. In each case we explore a variety of robust error measures and consistency weighting schemes that can be used to impose the desired constraints on the recovered needle-map. We provide an experimental assessment of the new shape-from-shading framework on both real world images and synthetic images with known ground truth surface normals. The main conclusion drawn from our analysis is that the data-closeness constraint improves the efficiency of shape-from-shading and that both the topographic and gradient consistency constraints improve the fidelity of the recovered needle-map

An Analysis of Kinetic Response Variability

Studies evaluating variability of force as a function of absolute force generated are synthesized. Inconsistencies in reported estimates of this relationship are viewed as a function of experimental constraints imposed. Typically, within-subject force variability increases at a negative accelerating rate with equal increments in force produced. Current pulse-step and impulse variability models are unable to accommodate this description, although the notion of efficiency is suggested as a useful construct to explain the description outlined

A structural analysis of the Orielton anticline Pembrokeshire

The results of a detailed investigation into the relationships between folds, faults and joints in the Orielton anticline are presented. The study continues the early structural work of Dixon (1921) and the stress analysis of the area made by Anderson (1951). The Orielton anticline is a compound and faulted Armorican fold largely affecting Upper Palaeozoic rooks. The structural pattern of the anticline developed during two major deformation phases: the first essentially corresponding to a period of folding and thrusting, the second to a period of wrench faulting. Within each phase, which is divisible, faulting occurred before jointing with joint sets not necessarily lying parallel to equivalent faults. The attitudes of both faults and joints depend on fold geometries. Faults are oriented relative to fold axial planes and axes, whilst joint attitudes are largely controlled by bedding dip and the plunge of the bedding - fracture cleavage intersection. It is tentatively suggested that the dependence of fracture attitudes upon fold geometries is due to the operation of residual stress systems. The dihedral angle between complementary shear planes has been investigated and shown to be consistently low, usually less than 50º. Regional tension joints appear to be absent. Joint orientations in collapsed blocks of Carboniferous Limestone enclosed in Triassio breccias show that all phases of the deformation belong to the Armorican orogeny

Self-estimation of Body Fat is More Accurate in College-age Males Compared to Females

Objective: To determine the effect of gender on the ability to accurately estimate one’s own body fat percentage. Participants: Fifty-five college-age males and 99 college-age females Methods: Participants estimated their own body fat percent before having their body composition measured using a BOD POD. Participants also completed a modified Social Physique Anxiety Scale (SPAS). Results: Estimated body fat was significantly lower compared to measured body fat percent in females (26.8±5.6% vs. 30.2±7.0%, p\u3c0.001) but not in males (16.8±6.8% vs. 18.1±8.3%, p=0.09). The mean difference between estimated and measured body fat was significantly higher for females compared to males (p\u3c0.001). There was a moderate, significant correlation found between measured body fat percent and SPAS score for males (r=0.331, p=0.014) and females (r=.427, p\u3c0.001). Conclusions: Males estimated their body fat percent more accurately than females. Despite these findings, 62% of males and 76% of females underestimated their body fat

Boson-Fermion coherence in a spherically symmetric harmonic trap

We consider the photoassociation of a low-density gas of quantum-degenerate trapped fermionic atoms into bosonic molecules in a spherically symmetric harmonic potential. For a dilute system and the photoassociation coupling energy small compared to the level separation of the trap, only those fermions in the single shell with Fermi energy are coupled to the bosonic molecular field. Introducing a collective pseudo-spin operator formalism we show that this system can then be mapped onto the Tavis-Cummings Hamiltonian of quantum optics, with an additional pairing interaction. By exact diagonalization of the Hamiltonian, we examine the ground state and low excitations of the Bose-Fermi system, and study the dynamics of the coherent coupling between atoms and molecules. In a semiclassical description of the system, the pairing interaction between fermions is shown to result in a self-trapping transition in the photoassociation, with a sudden suppression of the coherent oscillations between atoms and molecules. We also show that the full quantum dynamics of the system is dominated by quantum fluctuations in the vicinity of the self-trapping solution.Comment: 16 pages, 14 figure

Naturalistic Driving: User and Task Analysis

Cognitive Task Analysis and methods for analyzing Naturalistic Decision Making are powerful tools that can be applied to transportation research. In conjunction with simulators, these methods allow increased understanding of real user interactions with their in-vehicle systems, and the decision processes involved in the operational aspects of driving, navigating, and using infotainment support systems. Adopting this approach facilitates investigation of driver performance under a range of workload and stress conditions, which supports future development of a prototypical model that will encapsulate the cognitive and perceptual-motor demands of driving in the presence of situational stressors under both high- and low-workload conditions

Large-scale Star Formation Triggering in the Low-mass Arp 82 System: A Nearby Example of Galaxy Downsizing Based on UV/Optical/Mid-IR Imaging

As part of our Spitzer Spirals, Bridges, and Tails project to help understand the effects of galaxy interactions on star formation, we analyze GALEX ultraviolet, SARA optical, and Spitzer infrared images of the interacting galaxy pair Arp 82 (NGC 2535/6) and compare to a numerical simulation of the interaction. We investigate the multiwavelength properties of several individual star forming complexes (clumps). Using optical and UV colors, EW(Halpha), and population synthesis models we constrain the ages of the clumps and find that the median clump age is about 12 Myr. The clumps have masses ranging from a few times 10^6 to 10^9 solar masses. In general, the clumps in the tidal features have similar ages to those in the spiral region, but are less massive. The 8 micron and 24 micron luminosities are used to estimate the far-infrared luminosities and the star formation rates of the clumps. The total clump star formation rate is 2.0+/-0.8 solar masses per year, while the entire Arp 82 system is forming stars at a rate of 4.9+/-2.0 solar masses per year. We find, for the first time, stars in the HI arc to the southeast of the NGC 2535 disk. Population synthesis models indicate that all of the observed populations have young to intermediate ages. We conclude that although the gas disks and some old stars may have formed early-on, the progenitors are late-type or low surface brightness and the evolution of these galaxies was halted until the recent encounter.Comment: Accepted for publication in the AJ, 22 Figures, 5 Table

Determining the Electron-Phonon Coupling Strength in Correlated Electron Systems from Resonant Inelastic X-ray Scattering

We show that high resolution Resonant Inelastic X-ray Scattering (RIXS) provides direct, element-specific and momentum-resolved information on the electron-phonon (e-p) coupling strength. Our theoretical analysis demonstrates that the e-p coupling can be extracted from RIXS spectra by determining the differential phonon scattering cross section. An alternative, very direct manner to extract the coupling is to use the one and two-phonon loss ratio, which is governed by the e-p coupling strength and the core-hole life-time. This allows measurement of the e-p coupling on an absolute energy scale.Comment: 4 pages, 3 figure