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2007

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Articles 1231 - 1260 of 6758

Full-Text Articles in Physical Sciences and Mathematics

Self-Assembled Biomimetic Antireflection Coatings, Nicholas C. Linn, Chih-Hung Sun, Peng Jiang, Bin Jiang Sep 2007

Self-Assembled Biomimetic Antireflection Coatings, Nicholas C. Linn, Chih-Hung Sun, Peng Jiang, Bin Jiang

Mathematics and Statistics Faculty Publications and Presentations

The authors report a simple self-assembly technique for fabricating antireflection coatings that mimic antireflective moth eyes. Wafer-scale, nonclose-packed colloidal crystals with remarkable large hexagonal domains are created by a spin-coating technology. The resulting polymer-embedded colloidal crystals exhibit highly ordered surface modulation and can be used directly as templates to cast poly(dimethylsiloxane) (PDMS) molds. Moth-eye antireflection coatings with adjustable reflectivity can then be molded against the PDMS master. The specular reflection of replicated nipple arrays matches the theoretical prediction using a thin-film multilayer model. These biomimetic films may find important technological application in optical coatings and solar cells.


Combined D0 Measurements Constraining The Cp-Violating Phase And Width Difference In The BS0 System, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration Sep 2007

Combined D0 Measurements Constraining The Cp-Violating Phase And Width Difference In The BS0 System, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We combine the D0 measurement of the width difference between the light and heavy Bs0 mass eigenstates and of the CP-violating mixing phase determined from the time-dependent angular distributions in the Bs0J/ψφ decays along with the charge asymmetry in semileptonic decays also measured with the D0 detector. With the additional constraint from the world average of the flavor-specific Bs0 lifetime, we obtain ΔΓs ≡ (ΓL - ΓH) = 0.13 ± 0.09 ps-1 and ∣φs∣ = 2.44-0.39+0.47. The data sample corresponds …


Measurement Of The Tt̅ Production Cross Section In Pp̅ Collisions Using Dilepton Events, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration Sep 2007

Measurement Of The Tt̅ Production Cross Section In Pp̅ Collisions Using Dilepton Events, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We present a measurement of the tt̅ pair production cross section in pp̅ collisions at √s = 1.96 TeV utilizing approximately 425 pb-1 of data collected with the D0 detector. We consider decay channels containing two high pT charged leptons (either ℯ or μ) from leptonic decays of both top-daughter W bosons. These were gathered using four sets of selection criteria, three of which required that a pair of fully identified leptons (i.e., ℯμ, ℯℯ, or μμ) be found. The fourth approach imposed less restrictive criteria on one of the lepton candidates and required that at least …


Illuminating The Kapitza-Dirac Effect With Electron Matter Optics [Colloquium], Herman Batelaan Sep 2007

Illuminating The Kapitza-Dirac Effect With Electron Matter Optics [Colloquium], Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

The observation of the Kapitza-Dirac effect raises conceptual, theoretical, and experimental questions. The Kapitza-Dirac effect is often described as diffraction of free electrons from a standing wave of light or stimulated Compton scattering. However, for the two-color Kapitza-Dirac effect these two interpretations appear to lead to paradoxical conclusions. The discussion of this paradox deepens our understanding of both of these versions of the Kapitza-Dirac effect.


Higher-Order Threshold Corrections For Single Top Quark Production, Nikolaos Kidonakis Sep 2007

Higher-Order Threshold Corrections For Single Top Quark Production, Nikolaos Kidonakis

Faculty Articles

I discuss single top quark production at the Tevatron and the LHC. The cross section, including soft-gluon threshold corrections through NNNLO, is presented for each partonic channel. The higher-order corrections provide significant contributions to the single top cross sections at both colliders.


Paving Hessenberg Varieties By Affines, Julianna S. Tymoczko Sep 2007

Paving Hessenberg Varieties By Affines, Julianna S. Tymoczko

Mathematics Sciences: Faculty Publications

Regular nilpotent Hessenberg varieties form a family of subvarieties of the flag variety arising in the study of quantum cohomology, geometric representation theory, and numerical analysis. In this paper we construct a paving by affines of regular nilpotent Hessenberg varieties for all classical types, generalizing results of De Concini-Lusztig-Procesi and Kostant. This paving is in fact the intersection of a particular Bruhat decomposition with the Hessenberg variety. The nonempty cells of the paving and their dimensions are identified by combinatorial conditions on roots. We use the paving to prove these Hessenberg varieties have no odd-dimensional homology.


Thermal Stability Of Nanostructurally Stabilized Zirconium Oxide, Fereydoon Namavar, Gonghua Wang, Chin Li Cheung, Xiao Cheng Zeng, Renat F. Sabirianov, Wai-Ning Mei, Jaeil Bai, Joseph R. Brewer, Hani Haider, Kevin L. Garvin Sep 2007

Thermal Stability Of Nanostructurally Stabilized Zirconium Oxide, Fereydoon Namavar, Gonghua Wang, Chin Li Cheung, Xiao Cheng Zeng, Renat F. Sabirianov, Wai-Ning Mei, Jaeil Bai, Joseph R. Brewer, Hani Haider, Kevin L. Garvin

Physics Faculty Publications

Nanostructurally stabilized zirconium oxide (NSZ) hard transparent films were produced without chemical stabilizers by the ion beam assisted deposition technique (IBAD). A transmission electron microscopy study of the samples produced below 150 °C revealed that these films are composed of zirconium oxide (ZrO2) nanocrystallites of diameters 7.5 ± 2.3 nm. X-ray and selected-area electron diffraction studies suggested that the as-deposited films are consistent with cubic phase ZrO2. Rutherford backscattering spectroscopy (RBS) indicated the formation of stoichiometric ZrO2. The phase identity of these optically transparent NSZ films was in agreement with cubic ZrO2, …


A Survey Of Schema Matching Research, Roger Blake Sep 2007

A Survey Of Schema Matching Research, Roger Blake

College of Management Working Papers and Reports

Schema matching is the process of developing semantic matches between two or more schemas. The purpose of schema matching is generally either to merge two or more databases, or to enable queries on multiple, heterogeneous databases to be formulated on a single schema (Doan and Halevy 2005). This paper develops a taxonomy of schema matching approaches, classifying them as being based on a combination schema matching technique and the type of data used by those techniques. Schema matching techniques are categorized as being based on rules, learning, or ontology, and the type of data used is categorized as being based …


Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates Sep 2007

Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates

Theses and Dissertations

This thesis investigates security mechanisms for utility control and protection networks using IP-based protocol interaction. It proposes flexible, cost-effective solutions in strategic locations to protect transitioning legacy and full IP-standards architectures. It also demonstrates how operational signatures can be defined to enact organizationally-unique standard operating procedures for zero failure in environments with varying levels of uncertainty and trust. The research evaluates layering encryption, authentication, traffic filtering, content checks, and event correlation mechanisms over time-critical primary and backup control/protection signaling to prevent disruption by internal and external malicious activity or errors. Finally, it shows how a regional/national implementation can protect private …


Snell's Law Of Refraction Observed In Thermal Frontal Polymerization, John A. Pojman, Veronika Viner, Burcu Binici, Shanna Lavergne, Melanie Winsper, Dmitry Golovaty, Laura Gross Sep 2007

Snell's Law Of Refraction Observed In Thermal Frontal Polymerization, John A. Pojman, Veronika Viner, Burcu Binici, Shanna Lavergne, Melanie Winsper, Dmitry Golovaty, Laura Gross

Faculty Publications

We demonstrate that Snell’s law of refraction can be applied to thermal fronts propagating through a boundary between regions that support distinct frontal velocities. We use the free-radical frontal polymerization of a triacrylate with clay filler that allows for two domains containing two different concentrations of a peroxide initiator to be molded together. Because the polymerization reaction rates depend on the initiator concentration, the propagation speed is different in each domain. We study fronts propagating in two parallel strips in which the incident angle is 90°. Our data fit Snell’s law vr/vi = sin θr/sin …


A Three-Tier Knowledge Management Scheme For Software Engineering Support And Innovation, Richard Corbin, Christopher B. Dunbar, Qiuming Zhu Sep 2007

A Three-Tier Knowledge Management Scheme For Software Engineering Support And Innovation, Richard Corbin, Christopher B. Dunbar, Qiuming Zhu

Computer Science Faculty Publications

To ensure smooth and successful transition of software innovations to enterprise systems, it is critical to maintain proper levels of knowledge about the system configuration, the operational environment, and the technology in both existing and new systems. We present a three-tier knowledge management scheme through a systematic planning of actions spanning the transition processes in levels from conceptual exploration to prototype development, experimentation, and product evaluation. The three-tier scheme is an integrated effort for bridging the development and operation communities, maintaining stability to the operational performance, and adapting swiftly to software technology innovations. The scheme combines experiences of academic researches …


Tree Windbreaks In The Wheatbelt, Robert Sudmeyer, David Bicknell, Neil Coles Sep 2007

Tree Windbreaks In The Wheatbelt, Robert Sudmeyer, David Bicknell, Neil Coles

Bulletins 4000 -

Windbreaks comprising trees, or tree and shrub combinations, can offer many benefits on wheatbelt farms, particularly for protection of soil, stock, crops and pastures from damaging winds and erosion. Additional benefits include reduced evaporation from farm dams, reduced groundwater recharge, their use as nature conservation corridors and habitats, increased biodiversity including predators of crop and pasture pests, fire control, tree products and improved lifestyle and aesthetics.

In other areas and farming systems such as intensive horticulture, man-made windbreaks may be used, but their higher cost makes them unsuited for broadscale agriculture. Man-made windbreaks can be effective in reducing evaporative losses …


Environmental Controls On The Landscape-Scale Biogeography Of Stream Bacterial Communities, Noah Fierer, Jennifer L. Morse, Sean T. Berthrong, Emily S. Bernhardt, Robert B. Jackson Sep 2007

Environmental Controls On The Landscape-Scale Biogeography Of Stream Bacterial Communities, Noah Fierer, Jennifer L. Morse, Sean T. Berthrong, Emily S. Bernhardt, Robert B. Jackson

Environmental Science and Management Faculty Publications and Presentations

We determined the biogeographical distributions of stream bacteria and the biogeochemical factors that best explained heterogeneity for 23 locations within the Hubbard Brook watershed, a 3000-ha forested watershed in New Hampshire, USA. Our goal was to assess the factor, or set of factors, responsible for generating the biogeographical patterns exhibited by microorganisms at the landscape scale. We used DNA fingerprinting to characterize bacteria inhabiting fine benthic organic matter (FBOM) because of their important influence on stream nutrient dynamics. Across the watershed, streams of similar pH had similar FBOM bacterial communities. Streamwater pH was the single variable most strongly correlated with …


Managing The Recreational Catch Of Demersal Scalefish On The West Coast. Future Management Scenarios For Community Consideration, Jon Ford (Minister For Fisheries; The Kimberley, Pilbara And Gascoyne) Sep 2007

Managing The Recreational Catch Of Demersal Scalefish On The West Coast. Future Management Scenarios For Community Consideration, Jon Ford (Minister For Fisheries; The Kimberley, Pilbara And Gascoyne)

Fisheries management papers

This paper discusses the major issues around controlling the total recreational catch. It also considers some of the tools available to manage the catch to specific target levels. The sustainability of fish species must be a key driver. However, the impacts on the social amenity of recreational fishing must also be taken into account. Any particular tool, if used on its own and to its full extent, may be rather “blunt” in its application and its impacts unacceptable to large parts of the community. The most effective and acceptable management package will probably be a mix of tools, supported by …


Reclamation: Managing Water In The West, Steinaker Reservoir Normal Water Surface Elevation Increase Final Environmental Assessment And Finding Of No Significant Impact, U.S. Department Of The Interior, Bureau Of Reclamation, W. Russ Findlay Sep 2007

Reclamation: Managing Water In The West, Steinaker Reservoir Normal Water Surface Elevation Increase Final Environmental Assessment And Finding Of No Significant Impact, U.S. Department Of The Interior, Bureau Of Reclamation, W. Russ Findlay

All U.S. Government Documents (Utah Regional Depository)

This document is an environmental assessment (EA) of the proposal to raise the normal water surface elevation from 5517.8 feet above mean sea level (msl) to 5520.5 msl for Steinaker Reservoir in Uintah County, Utah. The Uintah Water Conservancy District (UWCD) has requested Bureau of Reclamation (Reclamation) authorization for this action. The Steinaker State Park, managed by the Utah Division of Parks and Recreation, maintains several campgrounds, an entrance station and other associated buildings and associated infrastructure. Modifications or relocations of some of these facilities would be needed in conjunction with an increase in the reservoir’s normal water surface elevation.


1139-3159_Nir_Spex, Dagny L. Looper Sep 2007

1139-3159_Nir_Spex, Dagny L. Looper

Publications and Research

No abstract provided.


Elongation Factor G Stabilizes The Hybrid-State Conformation Of The 70s Ribosome, P. Clint Spiegel, Dmitri N. Ermolenko, Harry F. Noller Sep 2007

Elongation Factor G Stabilizes The Hybrid-State Conformation Of The 70s Ribosome, P. Clint Spiegel, Dmitri N. Ermolenko, Harry F. Noller

Chemistry Faculty and Staff Publications

Following peptide bond formation, transfer RNAs (tRNAs) and messenger RNA (mRNA) are translocated through the ribosome, a process catalyzed by elongation factor EF-G. Here, we have used a combination of chemical footprinting, peptidyl transferase activity assays, and mRNA toeprinting to monitor the effects of EF-G on the positions of tRNA and mRNA relative to the A, P, and E sites of the ribosome in the presence of GTP, GDP, GDPNP, and fusidic acid. Chemical footprinting experiments show that binding of EF-G in the presence of the non-hydrolyzable GTP analog GDPNP or GDP·fusidic acid induces movement of a deacylated tRNA from …


Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas Sep 2007

Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas

Theses and Dissertations

Ant colony optimization algorithms have long been touted as providing an effective and efficient means of generating high quality solutions to NP-hard optimization problems. Unfortunately, while the structure of the algorithm is easy to parallelize, the nature and amount of communication required for parallel execution has meant that parallel implementations developed suffer from decreased solution quality, slower runtime performance, or both. This thesis explores a new strategy for ant colony parallelization that involves Area of Expertise (AOE) learning. The AOE concept is based on the idea that individual agents tend to gain knowledge of different areas of the search space …


A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge Sep 2007

A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge

Theses and Dissertations

Attack trees have been developed to describe processes by which malicious users attempt to exploit or break complex systems. Attack trees offer a method of decomposing, visualizing, and determining the cost or likelihood of attacks. Attack trees by themselves do not provide enough decision support to system defenders. This research develops the concept of using protection trees to offer a detailed risk analysis of a system. In addition to developing protection trees, this research improves the existing concept of attack trees and develops rule sets for the manipulation of metrics used in the security of complex systems. This research specifically …


Distribution And Disease Prevalence Of Feral Hogs In Missouri, R. Edwin Hartin, Mark R. Ryan, Tyler A. Campbell Sep 2007

Distribution And Disease Prevalence Of Feral Hogs In Missouri, R. Edwin Hartin, Mark R. Ryan, Tyler A. Campbell

United States Department of Agriculture Wildlife Services: Staff Publications

No attempts have been made to document the distribution of feral hogs (Sus scrofa) in Missouri. Also, antibody prevalence for pseudorabies virus and swine brucellosis have not been reported from Missouri. Our objectives were to characterize the current distribution of feral hogs in Missouri and to determine prevalence and distribution of feral hogs with antibodies against selected important diseases. We collected feral hog sighting data both from the public and Missouri Wildlife Services and Missouri Department of Conservation wildlife biologists. We determined prevalence of antibodies against pseudorabies virus, swine brucellosis, tularemia, and classical swine fever. From 2000 to …


Oneida Lake’S Cormorant Harassment Program – Frequently Asked Questions, Travis L. Devault Sep 2007

Oneida Lake’S Cormorant Harassment Program – Frequently Asked Questions, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Oneida Lake's cormorant harassment program, which began in 1998, is an outstanding example of an outstanding example of an effective government response to environmental problems. This program, administered by the United States Department of Agriculture, Wildlife Services Division, has contributed mightily to a major resurgence in the lake's game fish populations during the past three years. In the following article, USDA biologist Travis DeVault answers questions that often arise about the harassment program.


Adaptive And Economic Management Methods For Feral Hog Control In Florida, Richard M. Engeman, Bernice U. Constantin, Stephanie A. Shwiff, Henry T. Smith, John Woolard, John Allen, John Dunlap Sep 2007

Adaptive And Economic Management Methods For Feral Hog Control In Florida, Richard M. Engeman, Bernice U. Constantin, Stephanie A. Shwiff, Henry T. Smith, John Woolard, John Allen, John Dunlap

United States Department of Agriculture Wildlife Services: Staff Publications

Feral hogs (Sus scrofa) negatively impact the environment in most places around the world where they have been introduced into the wild. In many places, hog removal is essential to protect special habitats, in particular, wetlands. This paper describes techniques developed for use in adaptive management approaches to enhance hog removal efforts in Florida, as well as methods to evaluate the economic impacts from hog management. A valuable adaptive management tool that can be an easily applied index to monitor feral hog activity is track plots. This method has been effective for monitoring hog distribution and relative abundance, …


From The Field: An Extraordinary Patch Of Feral Hog Damage In Florida Before And After Initiating Hog Removal, John Woolard, Henry T. Smith, Jean Bourassa, Bernice U. Constantin, Daniel Griffin Sep 2007

From The Field: An Extraordinary Patch Of Feral Hog Damage In Florida Before And After Initiating Hog Removal, John Woolard, Henry T. Smith, Jean Bourassa, Bernice U. Constantin, Daniel Griffin

United States Department of Agriculture Wildlife Services: Staff Publications

Feral hogs (Sus scrofa) are a particularly destructive exotic species in the United States (U.S. Department of Agriculture 1999), including Florida, which, along with Hawaii, is one of 2 states cited as having the most severe invasive species problems (U.S. Congress 1993) in the country. First introduced to North America by the European colonists (Conover 2007) hogs were one of the first invasive exotic species to take hold in Florida. They can transmit disease to livestock (Hartin et al. 2007) and humans (Conover and Vail 2007). They impose a variety of negative environmental impacts, including habitat degradation and …


Crop Diversification Leads To Diverse Bird Problems In Hawaiian Agriculture, Marni E. Koopman, William C. Pitt Sep 2007

Crop Diversification Leads To Diverse Bird Problems In Hawaiian Agriculture, Marni E. Koopman, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

Over the last 20 years, Hawaii’s agriculture has shifted from a focus on sugar cane (Saccharum officinarum) and pineapples (Ananas comosus) produced on large farms to a diverse array of products produced on a multitude of smaller farms. This dramatic shift in production, in addition to the introduction of many new avian species, has resulted in a concomitant change in the problems faced by agriculture. We surveyed farmers to determine the extent of bird damage to crops, the species responsible, the crops most vulnerable, and control methods employed. Bird problems varied by island, but cardinals ( …


A Fence Design For Excluding Elk Without Impeding Other Wildlife, Kurt C. Vercauteren, Nathan W. Seward, Michael J. Lavelle, Justin W. Fischer, Gregory W. Phillips Sep 2007

A Fence Design For Excluding Elk Without Impeding Other Wildlife, Kurt C. Vercauteren, Nathan W. Seward, Michael J. Lavelle, Justin W. Fischer, Gregory W. Phillips

United States Department of Agriculture Wildlife Services: Staff Publications

Concentrated herbivory by elk (Cervus elaphus) can degrade vegetative communities and alter ecosystem processes. Areas severely damaged by elk are commonly protected with woven wire fence, which can exclude other animals. Complete exclusion and prevention of large mammal herbivory might not always be necessary to restore vegetative communities. We designed and evaluated a simple fence that excluded elk, but maintained access for deer and other species. We enclosed a 1-ha stand of quaking aspen (Populus tremuloides Michaux) with our fence in an area with a high density of elk. We monitored effectiveness of the fence with trackplots, …


Foraging Preferences Of Captive Canada Geese Related To Turfgrass Mixtures, Brian E. Washburn, Scott C. Barras, Thomas W. Seamans Sep 2007

Foraging Preferences Of Captive Canada Geese Related To Turfgrass Mixtures, Brian E. Washburn, Scott C. Barras, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

Overabundant populations of Canada geese (Branta canadensis) cause economic and safety concerns associated with collisions with civil and military aircraft. Habitat management techniques that reduce the use of airfield habitats by geese might reduce these concerns. The objective of this study was to determine if captive Canada geese exhibited a foraging preference between a vegetation mixture consisting mostly of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) versus an endophyte-infected tall fescue- (Festuca arundinacea) based vegetation mixture. We established 6 paired plots of perennial ryegrass-dominated and tall fescue-dominated mixtures at NASA …


Birds, George M. Linz, Jim Hanzel Sep 2007

Birds, George M. Linz, Jim Hanzel

United States Department of Agriculture Wildlife Services: Staff Publications

Sunflower, due to the easy accessibility and high nutritional value of its seed, is particularly vulnerable to damage by birds (Figure 101). Seeds are exposed and the large head serves as a perch during feeding. Sunflower seed is a preferred bird food because the seed contains many proteins and fats essential to their growth, molt, fat storage and weight maintenance processes. Although many species of birds feed in maturing sunflower fields, the greatest losses are caused by migrating flocks of red-winged blackbirds, yellow- headed blackbirds and common grackles (Figure 102). Significant losses can occur in fields near cattail marshes.


Evaluation Maps In Rational Homotopy, Yves Felix, Gregory Lupton Sep 2007

Evaluation Maps In Rational Homotopy, Yves Felix, Gregory Lupton

Mathematics and Statistics Faculty Publications

In the rational category of nilpotent complexes, let E be an H-space acting on a space X. With mild hypotheses we show that the action on the base point w: E→X factors through a map ΓE:SE→X, where S E is a finite product of odd-dimensional spheres and Γ E is a homotopy monomorphism. Among others, the following consequences are obtained:π∗(w)6=0 if and only if w is essential and H∗(w)6=0 if and only if X satisfies a strong splitting condition.


2,3,8,12,13-Penta­Meth­Oxy-5h-Dibenzo­[C,N]Acridin-7(6h)-One Toluene Solvate, Marlon R. Lutz Jr, Matthias Zeller, Daniel P. Becker Ph.D. Sep 2007

2,3,8,12,13-Penta­Meth­Oxy-5h-Dibenzo­[C,N]Acridin-7(6h)-One Toluene Solvate, Marlon R. Lutz Jr, Matthias Zeller, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

The title compound, C26H25NO6·C7H8, formed by an unexpected tandem reaction of Beckmann rearrangement, electrophilic aromatic addition and subsequent demethyl­ation, was crystallized as its toluene solvate. The crystal under investigation was found to be nonmerohedrally twinned by a rotation around the reciprocal axis [100]; the twin ratio refined to 0.688 (2):0.312 (2). The mol­ecule exhibits an unusual helical arrangement of three six-membered rings that are all connected at one central C atom. The helix effectively performs one full turn around this atom, and the thread pitch, as defined by the distance of the terminal C atoms of the helix, is 4.98 …


Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries Sep 2007

Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries

Theses and Dissertations

This research merges the hierarchical reinforcement learning (HRL) domain and the ant colony optimization (ACO) domain. The merger produces a HRL ACO algorithm capable of generating solutions for both domains. This research also provides two specific implementations of the new algorithm: the first a modification to Dietterich's MAXQ-Q HRL algorithm, the second a hierarchical ACO algorithm. These implementations generate faster results, with little to no significant change in the quality of solutions for the tested problem domains. The application of ACO to the MAXQ-Q algorithm replaces the reinforcement learning, Q-learning and SARSA, with the modified ant colony optimization method, Ant-Q. …