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Spherekit is a spatial interpolation software toolkit developed at NCGIA as part of Initiative 15: Multiple Roles of GIS in U.S. Global Change Research. This package features several unique capabilities and is freely distributed over the internet. Spherekit allows interpolation over continental or global scales by computing distances and orientations (among data and interpolation points) from geodesics on the surface of the globe. Conventional interpolations typically are based upon Euclidean distance in Cartesian 2-space which involve planar projections that produce distortions of some kind. In Spherekit, projections are applied only for display purposes after the interpolation has been carried out using spherical geometry. Users can select from several interpolation algorithms that have been adapted to the sphere: inverse distance weighting, thin plate splines, multiquadrics, triangulation, and kriging. Spherekit enables the user to incorporate knowledge or information about the processes that produce the underlying spatial variations into the interpolation model. A built-in equation editor and a collection of nonlinear transforms allow the user to create and experiment with new, physically meaningful variables from the independent and dependent variables available. This report is a reference guide to the software and is not intended to be read from cover to cover. Chapter 2 presents four examples of the use of the software. Chapter 3 takes a single example and presents the steps required to carry out an interpolation. Chapter 4 describes each of the menu options available in Spherekit. Chapter 5 provides a technical description of the interpolation algorithms. Finally, Chapter 6 describes the download and installation procedures.

The use of matched filters on hyperspectral data has made it possible to detect faint signatures. This study uses a modified k-means clustering to improve matched filter performance. Several simple bivariate cases are examined in detail, and the interaction of filtering and partitioning is discussed. We show that clustering can reduce within-class variance and group pixels with similar correlation structures. Both of these features improve filter performance. The traditional k-means algorithm is modified to work with a sample of the image at each iteration and is tested against two hyperspectral datasets. A new 'extreme' centroid initialization technique is introduced and shown to speed convergence. Several matched filtering formulations (the simple matched filter, the clutter matched filter, and the saturated matched filter) are compared for a variety of number of classes and synthetic hyperspectral images. The performance of the various clutter matched filter formulations is similar, all are about an order of magnitude better than the simple matched filter. Clustering is found to improve the performance of all matched filter formulations by a factor of two to five. Clustering in conjunction with clutter matched filtering can improve fifty-fold over the simple case, enabling very weak signals to be detected in hyperspectral images. Index Terms--Clustering, endmember decomposition, gas plumes, hyperspectral, image classification, image partitioning, matched filter, signal detection, spectral mixture analysis, trace element detection.

In patent litigation, courts frequently allow patent holders to access an accused infringer's trade secrets and other confidential technology. Those secrets may be relevant to claims of patent infringement. But the confidential access creates a risk that patent holders will misuse those secrets when their attorneys or experts wear two hats-- litigating the patent suit in court and working on patent applications in the same field as the accused infringer's confidential technology. These two hats allow certain attorneys and experts the opportunity to target the accused infringer's secret technology--either inadvertently or deliberately--by patenting it as their client's own intellectual property (IP). Several courts attempt to prevent this potential misuse of IP by imposing a patent prosecution bar, which typically forbids those with access to another party's confidential technology from working at all on patent applications in the same field. But the U.S. Court of Appeals for the Federal Circuit has created a flawed test for determining when a district court may impose prosecution bars. As implemented by most district courts, prosecution bars apply to only those attorneys and experts who are "competitive decisionmakers" and who have a history of working on patent applications. The test is based on a vague and underinclusive term and leaves those without a similar history free of a prosecution bar and positions them to target the other side's trade secrets with new patent claims. This targeted patenting undermines the IP system's channeling between patents and trade secrets. Channeling theory posits that inventors whose inventions are inherently transparent or at risk of being reverse engineered will choose patents and public disclosure over trade secrecy; but inventors whose inventions are inherently opaque may well choose trade secrecy. Both forms of IP promote innovation and deserve protection. Patent prosecution bars protect the integrity and incentives of both forms of IP by ensuring one party does not inadvertently or deliberately misappropriate the other's trade secret and grab a monopoly over technology it did not create. Despite courts and parties routinely struggling to apply the Federal Circuit's test, unfavorable standards of review have deterred appeals and made prosecution bars less visible to scholars. This Article fills a gap in the literature and proposes a new approach to patent prosecution bars that applies to everyone with confidential access. Instead of the current wholesale bars that prohibit any work on patent applications, the proposed model bar would prohibit only specific prosecution activities, such as drafting patent applications and claims, where attorneys or experts risk misusing their access to the other side's secrets. [ABSTRACT FROM AUTHOR]

A response by Molly E. Brown, Christopher C. Funk and James Verdin to a letter to the editor about the article "FOOD SECURITY UNDER CLIMATE CHANGE" in the February 1, 2008 issue is presented.