We present a system in which a flexible team of robots coordinate to assemble large, complex, and diverse structures autonomously. Our system operates across a wide range of spatial scales and tolerances, using a hierarchical perception architecture. For the successful execution of very precise assembly operations under initial uncertainty, our system starts with high-field of view but low accu...

The spatial structure of population subgroups is important for many reasons. Information on the spatial concentrations of people in particular groups may be used for guiding government policy and is central to understanding issues such as differential access to resources. In addition, any geographical analysis of populations is partly a function of the spatial scale of variation of subgroups of...

In Mediterranean-type ecosystems (MTEs), fire disturbance influences the distribution of most plant communities, and altered fire regimes may be more important than climate factors in shaping future MTE vegetation dynamics. Models that simulate the high-frequency fire and post-fire response strategies characteristic of these regions will be important tools for evaluating potential landscape cha...

I introduce a straightforward technique for the filtering of extended astronomical images into components of different spatial scales. For a positive original image, each component is positive definite, and the sum of all components equals the original image. In this way, the components are each individually suitable for flux measurements and broadband spectra calculations. I present an illustr...

The concept of local scale asserts that for a given class of psychophysical measurements, performance at any two visual field locations is equated by magnifying the targets by the local scale associated with each location. Local scale has been hypothesized to be equal to cortical magnification or alternatively to the linear density of receptors or ganglion cells. Here, we show that it is possib...

BRIAN M. WEIGEL*, LIZHU WANG*, PAUL W. RASMUSSEN*, JASON T. BUTCHER , PAUL M. STEWART , THOMAS P. SIMON § AND MICHAEL J. WILEY *Wisconsin Department of Natural Resources, Bureau of Integrated Science Services, Monona, WI, U.S.A. †U.S. Forest Service, Superior National Forest, Duluth, MN, U.S.A. ‡Troy State University, Department of Biological and Environmental Sciences, Troy, AL, U.S.A. §U.S. F...

Recent economic geography literature has underlined the role of tacit/local knowledge in embedding firms within their locales, characterised by the work on "learning regions", "territorial embeddedness", "institutional thickness" and "new industrial spaces". This paper contributes to this theoretical debate, using evidence from organisational restructuring of the U.S. department store industry ...

We perform a data analysis of trajectories of surface drifters deployed in the Adriatic Sea, and compare the results with a kinematic model. We show that, in the case of quasi-closed basins, the standard approach in terms of the diffusion coefficient gives poor information. In fact, the standard linear law for the dispersion cannot hold before finite-scale saturation effects set in. Other quant...

The rendering of participating media still forms a big challenge for computer graphics. This remark is particularly true for real-world clouds with their inhomogeneous density distributions, large range of spatial scales and different forms of appearance. We survey techniques for cloud visualization and classify them relative to the type of volume representation, lighting and rendering techniqu...

A typical aerospace composite component can be modeled on (at least) three different scales: (i) macroscale (structural level), (ii) mesoscale (laminate level), and (iii) microscale (the level of microconstituents). Additional scales can be introduced into the model. For example, the scale of material heterogeneity in each microphase, such as dislocations and grain boundaries, could be consider...