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

THE PRODUCTIVITY OF AGRICULTURAL RESEARCH AND EXTENSION EXPENDITURES IN THE SOUTHEAST

Research and Development/Tech Change/Emerging Technologies,

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 reconsideration of the risk sensitivity of U.S. banking organization subordinated debt spreads: a sample selection approach

The authors estimate a sample selection model over three distinct regulatory "regimes" when the treatment of bank bondholders (in the event of bank failures) differed substantially. They then estimate their selection model to test the strength of bond market discipline over these three regulatory regimes, finding that bank bond spreads are positively associated with bank risk measures during all three regimes, even during the too-big-to-fail period.Bank assets ; Debt management ; Banks and banking - Ratio analysis ; Deposit insurance

Centering Community College Students\u27 Experiences: A Multiple Methods Study of Multiple Measures for Writing Placement

Community colleges are trying to reform their placement procedures from use of a single placement test score to a system that collects multiple measures to be used either as a replacement solitary measure or in conjunction with other measures for more accurate placement into writing courses than what occurred with the placement test, which often resulted in disparate impact for students of color. In this study of multiple measures placement assessment for writing courses, I critique several large studies of community college multiple measures assessment for the lack of a community college perspective. The studies largely supported use of high school grade point average as a replacement for placement tests, but I found some of the reasoning to be faulty or unsupported by the data in the studies. I offer my own study of students at a community college in the Midwest as evidence of why high school grade point averages cannot be used fairly and accurately for all students in a community college system. In this study, I collected and analyzed multiple measures variables from 34 students and then supplemented it with qualitative data collected during student interviews to assess why for some of the students in the study, their paths were predictable and college credits were earned successfully but for others, the path was less linear, less predictable, with the collected measures not predicting success with any reliability. In a paradigm shift from most multiple measures research, I center qualitative data, particularly from the students who were not college-bound while in high school, as a means to explain the gaps in the quantitative data findings. In the final chapter, I interviewed four students from the initial study, where their stories built on my early conclusions regarding why high school transcripts and test scores are insufficient as solitary measures for writing placement for some community college students and suggest that we should also broaden our definitions of and measurement of success at community colleges

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

A study of the city relief department of the city of Concord, New Hampshire for the year - 1948

Thesis (M.S.)--Boston University, 1949. This item was digitized by the Internet Archive