Historic Wetlands Assessment Using Computerized Microdensitometric Analysis of Aerial Photographs

A technique has been designed and tested that permits the quantitative assessment of historic marsh conditions from black and white aerial photography. Utilizing a computerized scanning and writing Rotating Drum Microdensitometer (RDM) system, baseline marsh data has been derived by combining present day field data with computer analysis of present day and historical aerial photography. Quantitative information on the marsh grasses studied (Spartina alternifora - tall and short growth forms, Salt Hay - a mixture of Spartina patens and Distichlis spicata), their distributional patterns, and surface water locations were established. The RDM technique relates subtle optical density differences in a film emulsion to actual field conditions. Algorithms are then used to classify and map the marsh variables being studied. In this investigation, photographs were scanned using picture elements (pixels) as small as 25 µm per side. For 1:12,000 scale photographs, this translates to a ground equivalent area of 0.96 square feet. The RDM system measures the optical density of each pixel and assigns it one of 256 different density levels. This is approximately an order of magnitude greater than the human eye\u27s ability to differentiate subtle shades of gray. Once computer analysis is completed, the RDM system then prints the classification categories on to an emulsion, producing a film image that maps the marsh variables. Classification maps were produced by the RDM system for two geographically separate saline marshes. Each marsh was in excess of 100 acres. Using a Zoom Transfer Scope, the RDM classification maps were transferred and compared to historic wetland maps produced from manual interpretation of color infrared photographs and then extensively field surveyed. The wetland maps were produced by the New Jersey Department of Environmental Protection. Except for a few small areas where S. alterniflora was misclassified, vegetative cover classes were correctly classified. The vegetational boundaries and land/water interfaces were located with great accuracy

Generic Singularities of Robot Manipulators

The singularities of the differential kinematic map, i.e. of the manipulator Jacobian, are considered. The authors first examine the notion of a generic kinematic map, whose singularities form smooth manifolds of prescribed dimension in the joint space of the manipulator. For three-joint robots, an equivalent condition for genericity using determinants is derived. The condition lends itself to symbolic computation and is sufficient for the study of decoupled manipulators, i.e. manipulators that an be separated into a three-joint translating part and a three-joint orienting part. The results are illustrated by analyzing the singularities of two classes of three-joint positioning robots

CORBYS cognitive control architecture for robotic follower

In this paper the novel generic cognitive robot control architecture CORBYS is presented. The objective of the CORBYS architecture is the integration of high-level cognitive modules to support robot functioning in dynamic environments including interacting with humans. This paper presents the preliminary integration of the CORBYS architecture to support a robotic follower. Experimental results on high-level empowerment-based trajectory planning have demonstrated the effectiveness of ROS-based communication between distributed modules developed in a multi-site research environment as typical for distributed collaborative projects such as CORBYS

A Study on Effects of Process Parameters in Rapid Freeze Prototyping

Rapid Freeze Prototyping (RFP) is a relatively new solid freeform fabrication process, which builds a three-dimensional part according to a CAD model by depositing and freezing water droplets layer by layer. A study on the effects of RFP process parameters including the nozzle scanning speed, droplet size, and droplet frequency in building ice parts with a single-nozzle work head is made. Presented in this paper are the results of this study which indicate that these process parameters determine the ice layer thickness and ice line width, which in turn determine the surface roughness and the waiting time required after depositing each layer of water (i.e. between successive layers) during the ice part building process.This project is supported by a National Science Foundation Grant (DMI-0128313) and a Department of Education GAANN Fellowship Grant (P200A010446).Mechanical Engineerin

Estimation of the occupancy of butterflies in diverse biogeographic regions

AimWe explored the extent to which occupancy of butterflies within three biogeographic regions could be explained by vegetation structure and composition, topography and other environmental attributes; whether results were consistent among regions; and whether assumptions of closure were met with assemblage-level sampling designs. LocationChesapeake Bay Lowlands (Virginia), central Great Basin (Nevada) and western Great Basin (Nevada and California) (all USA). MethodsWe applied single-season occupancy models that either assumed closure or relaxed the closure assumption to data from 2013 and 2014 for 13-15 species in each region. ResultsMaximum single-year estimates of detection probabilities ranged from 0.14 to 0.99, and single-year occupancy from 0.28 to 0.98. The assumption of closure was met for a maximum of 54% of the species in a given region and year. Detection probabilities of \u3e90% of the species in each region increased as the categorical abundance of nectar or mud increased. Measures of the dominance or abundance of deciduous woody species and structural heterogeneity were included in the greatest number of occupancy models for the Chesapeake Bay Lowlands, which may in part reflect the intensity of browsing by white-tailed deer (Odocoileus virginianus). Elevation and precipitation were prominent covariates in occupancy models for Great Basin butterflies. Main conclusionsBecause occupancy models do not rely on captures or observations of multiple individuals in a population, they potentially can be applied to a relatively high proportion of the species in an assemblage. However, estimation of occupancy is complicated by taxonomic, temporal and spatial variation in phenology. In multiple, widely divergent ecosystems, all or some associations between covariates and detection probability or occupancy for at least one-third of the species could not be estimated, often because a given species rarely was detected at locations with relatively low or high values of a covariate. Despite their advantages, occupancy models may leave unexplained the environmental associations with the distributions of many species

Focusing of quantum gate interactions using dynamical decoupling

In 1995, Cirac and Zoller proposed the first concrete implementation of a small-scale quantum computer, using laser beams focused to micron spot sizes to address individual trapped ions in a linear crystal. Here we propose a method to focus entangling gate interactions, but driven by microwave fields, to micron-sized zones, corresponding to $10^{-5}$ microwave wavelengths. We demonstrate the ability to suppress the spin-dependent force using a single ion, and find the required interaction introduces $3.7(4)\times 10^{-4}$ error per emulated gate in a single-qubit benchmarking sequence. We model the scheme for a 17-qubit ion crystal, and find that any pair of ions should be addressable with an average crosstalk error of $\sim 10^{-5}$