Defender-assisted Evasion and Pursuit Maneuvers

Motivated by the possibilities afforded by active target defense, a 3-agent pursuit-evasion differential game involving an Attacker/Pursuer, a Target/Evader, and a Defender is considered. The Defender strives to assist the Target by intercepting the Attacker before the latter reaches the Target. A barrier surface in a reduced state space separates the winning regions of the Attacker and Target-Defender team. In this thesis, attention focuses primarily on the Attacker\u27s region of win where, under optimal Attacker play, the Defender cannot preclude the Attacker from capturing the Target. Both optimal and suboptimal strategies are investigated. This thesis uses several methods to breakdown and analyze the 3-player differential game

Establishment of Grasses on Sewage Sludge-Amended Strip Mine Spoils

Usefulness of native prairie and domesticated grasses in re-vegetating strip mine spoil and producing biomass was examined on 30-year old, recontoured spoil banks located near Canton, Illinois. Grasses were planted in the spring and fall on strip mine spoil and spoil amended with 333 MT/ha of dry sewage sludge. By the end of the second growing season, indiangrass [Sorghastrum nutans (L.) Nash] produced more biomass than the other warm-season grasses, switchgrass (Panicum virgatum L.) and little bluestem [Schizachyrium scoparium (Michx.) Nash], on the unamended plots, and no warm-season grasses survived on the sludge amended plots. Warm-season grasses were able to compete with weedy species on unamended sites, but two cool-season grasses, reed canarygrass (Phalaris arundinacea L.) and Kentucky 31 tall fescue (Festuca arundinacea Schreb.), produced more biomass on amended sites than on unamended sites

Establishment of Grasses on Sewage Sludge-Amended Strip Mine Spoils

Usefulness of native prairie and domesticated grasses in re-vegetating strip mine spoil and producing biomass was examined on 30-year old, recontoured spoil banks located near Canton, Illinois. Grasses were planted in the spring and fall on strip mine spoil and spoil amended with 333 MT/ha of dry sewage sludge. By the end of the second growing season, indiangrass [Sorghastrum nutans (L.) Nash] produced more biomass than the other warm-season grasses, switchgrass (Panicum virgatum L.) and little bluestem [Schizachyrium scoparium (Michx.) Nash], on the unamended plots, and no warm-season grasses survived on the sludge amended plots. Warm-season grasses were able to compete with weedy species on unamended sites, but two cool-season grasses, reed canarygrass (Phalaris arundinacea L.) and Kentucky 31 tall fescue (Festuca arundinacea Schreb.), produced more biomass on amended sites than on unamended sites

Magnetocentrifugal Winds in 3D: Nonaxisymmetric Steady State

Outflows can be loaded and accelerated to high speeds along rapidly rotating, open magnetic field lines by centrifugal forces. Whether such magnetocentrifugally driven winds are stable is a longstanding theoretical problem. As a step towards addressing this problem, we perform the first large-scale 3D MHD simulations that extend to a distance $\sim 10^2$ times beyond the launching region, starting from steady 2D (axisymmetric) solutions. In an attempt to drive the wind unstable, we increase the mass loading on one half of the launching surface by a factor of $\sqrt{10}$, and reduce it by the same factor on the other half. The evolution of the perturbed wind is followed numerically. We find no evidence for any rapidly growing instability that could disrupt the wind during the launching and initial phase of propagation, even when the magnetic field of the magnetocentrifugal wind is toroidally dominated all the way to the launching surface. The strongly perturbed wind settles into a new steady state, with a highly asymmetric mass distribution. The distribution of magnetic field strength is, in contrast, much more symmetric. We discuss possible reasons for the apparent stability, including stabilization by an axial poloidal magnetic field, which is required to bend field lines away from the vertical direction and produce a magnetocentrifugal wind in the first place.Comment: 10 pages, 2 figures, accepted for publication in ApJ

Diabetes management before and after cancer diagnosis: missed opportunity

Background Few studies have examined the management of comorbidities in cancer patients. This study used population-based data to estimate the guideline concordance rates for diabetes management before and after cancer diagnosis and examined if diabetes management services among cancer patients was associated with characteristics of the hospital where the patient was treated. Methods We linked 2005-2009 Medicare claims data to information on 2,707 breast and colorectal cancers patients in state cancer registry files. Multivariate logistic regression models examined hospital characteristics associated with receipt of diabetes management care after cancer diagnosis. Results The rates of HbAlc testing, LDL-C testing, and retinal eye exam decreased from 72.7%, 79.6%, and 57.9% before cancer diagnosis to 58.3%, 69.5%, and 55.8% after diagnosis. The pre- and post-diagnosis diabetes management care was not significantly different by hospital characteristics in the bivariate analysis except for that the distance between residence and hospital was negatively related to retinal eye exam after diagnosis (P Conclusions Cancer patients received fewer diabetes management care after diagnosis than prior to diagnosis, even for those who were treated in large comprehensive centers. This may reflect a missed opportunity to connect diabetic cancer patients to diabetes care. This study provides benchmarks to measure improvements in comorbidity management among cancer patients

Using quasirandom numbers in neural networks

We present a novel training algorithm for a feed forward neural network with a single hidden layer of nodes (i.e., two layers of connection weights). Our algorithm is capable of training networks for hard problems, such as the classic two-spirals problem. The weights in the first layer are determined using a quasirandom number generator. These weights are frozen---they are never modified during the training process. The second layer of weights is trained as a simple linear discriminator using methods such as the pseudo-inverse, with possible iterations. We also study the problem of reducing the hidden layer: pruning low-weight nodes and a genetic algorithm search for good subsets

Human Factor and Usability Testing of a Binocular Optical Coherence Tomography System

PURPOSE: To perform usability testing of a binocular optical coherence tomography (OCT) prototype to predict its function in a clinical setting, and to identify any potential user errors, especially in an elderly and visually impaired population. METHODS: Forty-five participants with chronic eye disease (mean age 62.7 years) and 15 healthy controls (mean age 53 years) underwent automated eye examination using the prototype. Examination included 'whole-eye' OCT, ocular motility, visual acuity measurement, perimetry, and pupillometry. Interviews were conducted to assess the subjective appeal and ease of use for this cohort of first-time users. RESULTS: All participants completed the full suite of tests. Eighty-one percent of the chronic eye disease group, and 79% of healthy controls, found the prototype easier to use than common technologies, such as smartphones. Overall, 86% described the device to be appealing for use in a clinical setting. There was no statistically significant difference in the total time taken to complete the examination between participants with chronic eye disease (median 702 seconds) and healthy volunteers (median 637 seconds) (P = 0.81). CONCLUSION: On their first use, elderly and visually impaired users completed the automated examination without assistance. Binocular OCT has the potential to perform a comprehensive eye examination in an automated manner, and thus improve the efficiency and quality of eye care. TRANSLATIONAL RELEVANCE: A usable binocular OCT system has been developed that can be administered in an automated manner. We have identified areas that would benefit from further development to guide the translation of this technology into clinical practice