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1999

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Full-Text Articles in Physical Sciences and Mathematics

Experimental And Phenomenological Study Of Persistent Photoconductivity In Yba2cu3o6 Thin Films, Daniel-Dennis Mcalevy Bubb Dec 1999

Experimental And Phenomenological Study Of Persistent Photoconductivity In Yba2cu3o6 Thin Films, Daniel-Dennis Mcalevy Bubb

Dissertations

Persistent Photoconductivity in YBa2Cu3O6+x thin films is studied by means of infrared photoconductivity measurements after the films have been illuminated with visible light at low temperature. Experimentally, the effect is characterized by the samples' electrical response to infrared light, either causing the resistance to decrease or increase.

A cellular automata model is proposed in explanation of these results and is shown to be consistent with current experimental understanding of this unusual effect, both our results and those of others. The cellular automata model may have application to other unusual optical phenomena exhibited by YBa ...


A Mathematical Model Of Wheelchair Racing, Susan J. Schenk Dec 1999

A Mathematical Model Of Wheelchair Racing, Susan J. Schenk

Dissertations

Wheelchair racing strokes are very complicated movements, which involve a coupling between the athlete and his or her racing chair. Each body segment, as well as the wheel, follows a distinct trajectory as the motion is performed. Understanding the kinematics and kinetics of various stroke techniques would provide the athletes and their coaches with information, which could help guide the racers toward improved performances.

In this thesis, a mathematical model is developed, which is capable of providing such valuable kinematic and kinetic information. This two-dimensional model represents the body segments as a coupled pendulum system of point masses and the ...


A Qualitative Study Of Technology Transfer In Sustainable Green Manufacturing, Susan Muldowney Dec 1999

A Qualitative Study Of Technology Transfer In Sustainable Green Manufacturing, Susan Muldowney

Theses

The Sustainable Green Manufacturing Project is an initiative of the United States Army to develop environmentally-friendly technologies for Army-designated facilities. In pursuit of this goal, the Army has sought the research capabilities and expertise of outside organizations including the New Jersey Institute of Technology and Concurrent Technologies Corporation. The groups interact and exchange knowledge and tools with each other as well as with potential end users of the green technology. This exchange of knowledge and tools is known as technology transfer.

Researchers and Subject Matter Experts who are working on the SGM Project were interviewed in order to learn about ...


A Study Of Platinum, Palladium, Bismuth, Copper, And Silver For The Potentiometric Determination Of Chlorine, Maria A. Gottwald Dec 1999

A Study Of Platinum, Palladium, Bismuth, Copper, And Silver For The Potentiometric Determination Of Chlorine, Maria A. Gottwald

Theses

This research was undertaken to determine which metals would be suitable to be used as electrodes for the determination of the concentration of chlorine in aqueous solutions at various pH levels. Platinum, palladium, bismuth, copper and silver electrodes were constructed and tested to determine their applicability for measuring the concentration of chlorine in drinking water, waste water treatment plant effluent, and swimming pools. Buffer solutions were used which varied in pH from 7 to 8, and in cHorine concentration from 0 to 10 ppm. In addition, the potential variation over time was observed for each electrode in the solutions.

Platinum ...


Polymer Pyrolysis And Oxidation Studies In A Continuous Feed And Flow Reactor : Cellulose, Polystyrene, And Polyethylene, Byung-Ik Park Dec 1999

Polymer Pyrolysis And Oxidation Studies In A Continuous Feed And Flow Reactor : Cellulose, Polystyrene, And Polyethylene, Byung-Ik Park

Dissertations

A dual zone, continuous feed tubular reactor is developed to assessthe potential for formation of products from incomplete combustion in thermal oxidation of common polymers. Solid polymer powder (cellulose,polystyrene, or polyethylene) is fed continuously into a volatilization oven where it fragments and vaporizes under continuous steady state conditions. The gas phase polymer fragments flow directly into a second, main flow reactor oven and undergo further pyrolysis and oxidation reaction. Temperatures in the main flow reactor are varied independently of the volatilization zone to observe conditions needed to convert the initial polymer fragmentsto CO2 and H2O. Combustion ...


Experiment, Thermodynamic Properties And Modeling On Combustion Of Methyl Tert-Butyl Ether : Isobutane And Isobutene And Thermodynamic Properties Of Chloro Alkanes And Alkenes, Chiung-Ju Chen Dec 1999

Experiment, Thermodynamic Properties And Modeling On Combustion Of Methyl Tert-Butyl Ether : Isobutane And Isobutene And Thermodynamic Properties Of Chloro Alkanes And Alkenes, Chiung-Ju Chen

Dissertations

The reaction systems: methyl tert-butyl ether (MTBE) unimolecular decomposition, MTBE radicals + O2, tert-butyl radical +O2, isobutene + HOO. (HO2),isobutene + OH, sobutene-OH adducts + O2, and allylic isobutenyl radical + O2, are important systems in the understanding the oxidation chemistry of MTBE, tertiary butyl radical (C3C.), and sobutene, are analyzed. Thermochemical parameters are determined by ah initio Møller-Plesset (MP2(full)/6-31g(d)), complete basis set model chemistry (CBS-4 and CBS-q with MP2(full)/6-31g(d) and B3LYP/6-31g(d) optimized geometries), density functional (B3LYP/631g(d)), semi-empirical MOPAC (PM3) molecular orbital calculations, and by group additivity estimation ...


Collaborative Software Agents Support For The Texpros Document Management System, Jrtian Lin Dec 1999

Collaborative Software Agents Support For The Texpros Document Management System, Jrtian Lin

Dissertations

This dissertation investigates the use of active rules that are embedded in markup documents. Active rules are used in a markup representation by integrating Collaborative Software Agents with TEXPROS (abbreviation for TEXt PROcessing System) [Liu and Ng 1996] to create a powerful distributed document management system. Such markup documents with embedded active rules are called Active Documents. For fast retrieval purposes, when we need to generate a customized Internet folder organization, we first define the Folder Organization Query Language (FO-QL) to solve data categorization problems. FO-QL defines the folder organization query process that automatically retrieves links of documents deposited into ...


Hytexpros : A Hypermedia Information Retrieval System, Hong Shen Dec 1999

Hytexpros : A Hypermedia Information Retrieval System, Hong Shen

Dissertations

The Hypermedia information retrieval system makes use of the specific capabilities of hypermedia systems with information retrieval operations and provides new kind of information management tools. It combines both hypermedia and information retrieval to offer end-users the possibility of navigating, browsing and searching a large collection of documents to satisfy an information need. TEXPROS is an intelligent document processing and retrieval system that supports storing, extracting, classifying, categorizing, retrieval and browsing enterprise information. TEXPROS is a perfect application to apply hypermedia information retrieval techniques. In this dissertation, we extend TEXPROS to a hypermedia information retrieval system called HyTEXPROS with hypertext ...


To Who Or What Do We Owe Sustainable Development? A Search For An Ethical Framework For Sustainable Development, Mia Soderlund Dec 1999

To Who Or What Do We Owe Sustainable Development? A Search For An Ethical Framework For Sustainable Development, Mia Soderlund

Theses

This thesis focuses on the ethical dimension of sustainable development as described in the Bruntland report. According to this report, we do have certain moral obligations to future generations. This thesis asks whether traditional moral philosophy, such as utilitarian and contractarian theories, can justify moral obligations to future generations, and if they can serve as ethical frameworks for sustainable development. The basic idea with sustainable development is to create a balance between society, the environment and the economy. If the environment is ascribed instrumental value, which is the case with traditional moral philosophy then there is no balance, because its ...


Automatic Categorization Of Abstracts Through Bayesian Networks, William Ramirez Dec 1999

Automatic Categorization Of Abstracts Through Bayesian Networks, William Ramirez

Theses

This thesis presents a method for assigning abstracts of Artificial Intelligence papers to their area of the field. The technique is implemented by the use of a Bayesian network where relevant keywords extracted from the abstract being categorized, are entered as evidence and inferencing is made to determine potential subject areas. The structure of the Bayesian network represents the causal relationship between Artificial Intelligence keywords and subject areas. Keyword components of the network are selected from precategorized abstracts. The work reported here is part of a larger project to automatically assign papers to reviewers for Artificial Intelligence conferences. The process ...


Analysis Of Clustering Algorithms For Spike Sorting Of Multiunit Extracellular Recordings, Jayesh Rege Dec 1999

Analysis Of Clustering Algorithms For Spike Sorting Of Multiunit Extracellular Recordings, Jayesh Rege

Theses

Various techniques have been considered in the past to identify distinct spike shapes from mulitunit extracellular recording. These techniques involve adaptive filtering techniques or template matching techniques or hierarchical clustering techniques. In this investigation, we have used Principal Component Analysis followed by various clustering techniques to identify distinct spike shapes. The amplitude filter is used to separate spikes from background neuronal activity. The correlation matrix of the spike data is used to compute principal component wave forms. Each spike is thus represented by the coefficients of principal components. Then, We have used agglomorative hierarchical clustering algorithm to perform the initial ...


Integration Of Multi Lifecycle Assessment And Design For Environment Database Using Relational Moddel Concepts, Bhagyashree Suratran Dec 1999

Integration Of Multi Lifecycle Assessment And Design For Environment Database Using Relational Moddel Concepts, Bhagyashree Suratran

Theses

Multi-lifecycle Assessment (MLCA) systematically considers and quantifies the consumption of resources and the environmental impact associated with a product or process. Design challenges posed by a multi-lifecycle strategy are significantly more complex than traditional product design. The designer must look forward in time to maximize the product's end-of-life yield of assemblies, parts and materials while looking backward to the world of existing products for feedstock sources for the current design. As MLCA and DEE share some common data items, such as, part geometry, material and manufacturing process, it is advantageous to integrate the database for MLCA and DEE. The ...


A Visualization System For Information Retrieval And Mining In High Dimensional Databases, Xinhuan Zheng Dec 1999

A Visualization System For Information Retrieval And Mining In High Dimensional Databases, Xinhuan Zheng

Theses

In this thesis, we present a search engine capable of giving good heuristic answers to the queries on a structural database. A structural database holds structural objects, e.g., protein secondary and tertiary structures, 3D molecules, phylogenetic trees, neuroanatomical networks, parse trees, CAD/CAM parts, and XML documents. Answering queries on such databases often requires solving variants of the graph isomorphism or subisomorphism problems. We also describe a graphic user interface which interacts with users to facilitate visualizing query results. We use 3D molecules (graphs) as illustrating examples, though our prototype is able to handle many other different types of ...


A Comparison Of Field-Delineated Wetlands To The New Jersey Freshwater Wetland Maps, David P. Moskowitz Dec 1999

A Comparison Of Field-Delineated Wetlands To The New Jersey Freshwater Wetland Maps, David P. Moskowitz

Theses

A comparison of the New Jersey Freshwater Wetland maps to field-delineated wetlands was undertaken to assess the accuracy of the Freshwater Wetland maps. The evaluation revealed substantial differences in the amount of wetland acreage on the Freshwater Wetland maps compared to field-verified wetlands. Forty study sites comprising 21,877 acres (8,854h) were evaluated. Of these, twenty-seven were overmapped (more wetland acreage than was field-verified), and thirteen were undermapped. Forty-three percent had mapping discrepancies at or above fifty percent; when modified land designations were included as wetlands, the number of sites at this threshold increased to fifty percent.

Paper copies ...


Dynamics Of The Dbi Spike Soliton, David Kastor, Jennie Traschen Dec 1999

Dynamics Of The Dbi Spike Soliton, David Kastor, Jennie Traschen

David Kastor

We compare oscillations of a fundamental string ending on a D3-brane in two different settings: (1) a test-string radially threading the horizon of an extremal black D3-brane and (2) the spike soliton of the DBI effective action for a D3-brane. Previous work has shown that overall transverse modes of the test-string appear as l=0 modes of the transverse scalar fields of the DBI system. We identify DBI world-volume degrees of freedom that have dynamics matching those of the test-string relative transverse modes. We show that there is a map, resembling T-duality, between relative and overall transverse modes for the ...


Viscoelastic Depinning Of Driven Systems: Mean-Field Plastic Scallops, M. Cristina Marchetti, Alan Middleton, Thomas Prellberg Dec 1999

Viscoelastic Depinning Of Driven Systems: Mean-Field Plastic Scallops, M. Cristina Marchetti, Alan Middleton, Thomas Prellberg

Physics

We have investigated the mean field dynamics of an overdamped viscoelastic medium driven through quenched disorder. The model introduced incorporates coexistence of pinned and sliding degrees of freedom and can exhibit continuous elastic depinning or first order hysteretic depinning. Numerical simulations indicate mean field instabilities that correspond to macroscopic stick-slip events and lead to premature switching. The model is relevant for the dynamics of driven vortex arrays in superconductors and other extended disordered systems.


A Continuous Sampling Air-Icp For Metals Emission Monitoring, David P. Baldwin, Daniel S. Zamzow, David E. Eckels, George P. Miller Dec 1999

A Continuous Sampling Air-Icp For Metals Emission Monitoring, David P. Baldwin, Daniel S. Zamzow, David E. Eckels, George P. Miller

Chemistry Conference Papers, Posters and Presentations

An air-inductively coupled plasma (air-ICP) system has been developed for continuous sampling and monitoring of metals as a continuous emission monitor (CEM). The plasma is contained in a metal enclosure to allow reduced-pressure operation. The enclosure and plasma are operated at a pressure slightly less than atmospheric using a Roots blower, so that sample gas is continuously drawn into the plasma. A Teflon sampling chamber, equipped with a sampling pump, is connected to the stack that is to be monitored to isokinetically sample gas from the exhaust line and introduce the sample into the air-ICP. Optical emission from metals in ...


The Reflectance Spectrum Of Human Skin, Elli Angelopoulou Dec 1999

The Reflectance Spectrum Of Human Skin, Elli Angelopoulou

Technical Reports (CIS)

The automated detection of human skin has become an important task for machine vision systems. Prior vision and graphics research on this topic has primarily focused on images acquired with conventional color cameras. Formal spectrographic analyses have largely been undertaken in the medical domain and focus on the detection of pathology. We have constructed a facility capable of producing accurate, dense and repeatable reflectance measurements. The light reflected from the skin is measured using a high resolution, high accuracy spectrograph under precisely calibrated lighting conditions. This paper presents observations from the first body of data gathered at this facility. From ...


Emissions Of Formaldehyde, Acetic Acid, Methanol, And Other Trace Gases From Biomass Fires In North Carolina Measured By Airborne Fourier Transform Infrared Spectroscopy, Robert J. Yokelson, Jon G. Goode, Darold E. Ward, Ronald A. Susott, Ronald E. Babbitt, D. D. Wade, Issac T. Bertschi, David W. T. Griffith, Wei Min Hao Dec 1999

Emissions Of Formaldehyde, Acetic Acid, Methanol, And Other Trace Gases From Biomass Fires In North Carolina Measured By Airborne Fourier Transform Infrared Spectroscopy, Robert J. Yokelson, Jon G. Goode, Darold E. Ward, Ronald A. Susott, Ronald E. Babbitt, D. D. Wade, Issac T. Bertschi, David W. T. Griffith, Wei Min Hao

Chemistry and Biochemistry Faculty Publications

Biomass burning is an important source of many trace gases in the global troposphere. We have constructed an airborne trace gas measurement system consisting of a Fourier transform infrared spectrometer (FTIR) coupled to a “flow-through” multipass cell (AFTIR) and installed it on a U.S. Department of Agriculture Forest Service King Air B-90. The first measurements with the new system were conducted in North Carolina during April 1997 on large, isolated biomass fire plumes. Simultaneous measurements included Global Positioning System (GPS); airborne sonde; particle light scattering, CO, and CO2; and integrated filter and canister samples. AFTIR spectra acquired within ...


Nanocomposite Copt:C Films For Extremely High-Density Recording, M. Yu, Yi Liu, A. Moser, D. Weller, David J. Sellmyer Dec 1999

Nanocomposite Copt:C Films For Extremely High-Density Recording, M. Yu, Yi Liu, A. Moser, D. Weller, David J. Sellmyer

David Sellmyer Publications

Nanocomposite CoPt:C films were investigated as potential media for extremely high-density recording. An annealing temperature of over 600 °C is necessary to form nanocomposite CoPt:C films consisting of C matrix and fct CoPt nanocrystallites with grain sizes of 8–20 nm and coercivities of 3–12 kOe. Coercivity and grain size increase with increasing annealing temperature and decreasing C concentration and they are insensitive to film thickness. The average activation volumes are about 0.9×10-18 cm3. The properties of these nanocomposite CoPt:C films can be tailored to satisfy the thermal stability, coercivity, and media ...


Electrical Resistivity Of A Thin Metallic Film, Horacio E. Camblong Dec 1999

Electrical Resistivity Of A Thin Metallic Film, Horacio E. Camblong

Physics and Astronomy

The electrical resistivity of a pure sample of a thin metallic film is found to depend on the boundary conditions. This conclusion is supported by a free-electron model calculation and confirmed by an ab initio relativistic Korringa-Kohn-Rostoker computation. The low-temperature resistivity is found to be zero for a free-standing film (reflecting boundary conditions) but nonzero when the film is sandwiched between two semi-infinite samples of the same material (outgoing boundary conditions). In the latter case, this resistivity scales inversely with the number of monolayers and is due to the background diffusive scattering by a finite lattice.


Breeding Bird Census On Four Shelterwood-Cut Stands In Buckingham County, Virginia, Sally Ann Statham Dec 1999

Breeding Bird Census On Four Shelterwood-Cut Stands In Buckingham County, Virginia, Sally Ann Statham

Theses, Dissertations & Honors Papers

The Breeding Bird Census (BBC) technique was used to study breeding bird populations on two paired shelter wood-cut oak stands in Buckingham County, Virginia. The four plots are part of a study to determine oak regeneration following controlled burns in the Virginia piedmont. There is an interest in determining how shelter wood-cut plots affect the breeding birds of Virginia. A total of twenty-seven bird species established and defended territories among the four plots. Ten bird species defended territories on all four plots. All of these species were birds characteristic of forest habitats.


Material-Independent Determination Of Anchoring Properties On Rubbed Polyimide Surfaces, Bharat R. Acharya, Jae-Hoon Kim, Satyendra Kumar Dec 1999

Material-Independent Determination Of Anchoring Properties On Rubbed Polyimide Surfaces, Bharat R. Acharya, Jae-Hoon Kim, Satyendra Kumar

Physics Publications

A material-independent method for determining liquid-crystal (LC) anchoring energy on rubbed polyimide (PI) surfaces has been devised. This method exploits the changes in the easy axis of rubbed PI film induced by exposure to linearly polarized UV (LPUV) Light. The distribution of PI chains in a rubbed film is approximated by a Gaussian function and its width determined from the measured rotation of the LC easy axis as a function of exposure time. A quasimicroscopic free energy of the LC-substrate interface is used to model LC anchoring properties. The experimental and calculated values of the azimuthal anchoring energy are in ...


Quasicrystalline Nature Of Quasicrystal Surfaces: A Photoemission Study, D. Naumović, P. Aebi, :L. Schlapbach, C. Beeli, Thomas A. Lograsso, Dwight W. Delaney Dec 1999

Quasicrystalline Nature Of Quasicrystal Surfaces: A Photoemission Study, D. Naumović, P. Aebi, :L. Schlapbach, C. Beeli, Thomas A. Lograsso, Dwight W. Delaney

Ames Laboratory Publications

Differently prepared surfaces of quasicrystalline i-Al-Pd-Mn are analyzed using angle-resolved photoemission in the x-ray andultraviolet range of photon energies. Depending on the preparation, we find both surfaces with crystalline structure and metallic character, and surfaces with quasicrystalline structural fingerprints and a suppressed density of states at the Fermi level, compatible with a pseudogap.


A Patching Model For Surface Tension Of Spherical Droplet And Tolman Length. Ii, T.V. Bykov, Xiao Cheng Zeng Dec 1999

A Patching Model For Surface Tension Of Spherical Droplet And Tolman Length. Ii, T.V. Bykov, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

In the framework of density functional theory (DFT), two patching models for the density profile of spherical liquid droplet are developed. The patching is based on analytical expressions of the asymptote of the density profiles. The first model leads to analytic expressions of the Tolman length and the effective rigidity constant, from which the temperature dependence of the Tolman length and effective rigidity constant can be determined. The second model is developed particularly for small spherical droplets, from which the dependence of chemical potential and the surface tension of the droplet on the radius are obtained. The results are compared ...


Minmax Trees: Efficient Relational Operation Support For Hierarchical Data Exploration, Ionel D. Stroe, Elke A. Rundensteiner, Matthew O. Ward Dec 1999

Minmax Trees: Efficient Relational Operation Support For Hierarchical Data Exploration, Ionel D. Stroe, Elke A. Rundensteiner, Matthew O. Ward

Computer Science Faculty Publications

This paper presents a new method for implementing hierarchical navigation operations in relational database systems as required for applications such as interactive visual explorations over large datasets. A particular class of recursive unions of joins and divisions that operate on hierarchies has been identified. By using adequate pre-computation (i.e., organizing the hierarchical structure as what we called a MinMax tree), the recursive processing of the operations in this class is shown to be reducible to range queries. Extensions of the method for non-tree as well as dynamic hierarchies have also been designed. We implemented our technique using Oracle 7 ...


Fundamental Plane Distances To Early-Type Field Galaxies In The South Equatorial Strip. I. The Spectroscopic Data, K. R. Müller, G. Wegner, S. Raychaudhury, W. Freudling Dec 1999

Fundamental Plane Distances To Early-Type Field Galaxies In The South Equatorial Strip. I. The Spectroscopic Data, K. R. Müller, G. Wegner, S. Raychaudhury, W. Freudling

Open Dartmouth: Faculty Open Access Articles

Radial velocities and central velocity dispersions are derived for 238 E/S0 galaxies from medium-resolution spectroscopy. New spectroscopic data have been obtained as part of a study of the Fundamental Plane distances and peculiar motions of early-type galaxies in three selected directions of the South Equatorial Strip, undertaken in order to investigate the reality of large-scale streaming motion; results of this study have been reported in M\"uller $et$ $al.$ (1998). The new APM South Equatorial Strip Catalog (−17.5 < δ < +2.5) was used to select the sample of field galaxies in three directions: (1) 15h10 – 16h10; (2) 20h30 – 21h50; (3) 00h10 – 01h30. The spectra obtained have a median S/N per ̊A of 23, an in- strumental resolution (FWHM) of ∼ 4 ̊A, and the spectro- graph resolution (dispersion) is ∼ 100 km s−1. The Fourier cross-correlation method was used to derive the radial ve- locities and velocity dispersions. The velocity dispersions have been corrected for the size of the aperture and for the galaxy effective radius. Comparisons of the derived radial velocities with data from the literature show that our values are accurate to 40 km s−1. A comparison with results from Jørgensen et al. (1995) shows that the derived central velocity dispersion have an rms scatter of 0.036 in log σ. There is no offset relative to the velocity dispersions of Davies et al. (1987).


Interaction Second Virial Coefficients From A Recent H2-Co Potential Energy Surface, J. Gottfried, George C. Mcbane Dec 1999

Interaction Second Virial Coefficients From A Recent H2-Co Potential Energy Surface, J. Gottfried, George C. Mcbane

Peer Reviewed Articles

No abstract provided.


Langmuir Monolayers As Disordered Solids: Disorder And Elastic Fluctuations In Mesophases , Tadeusz Luty, Craig J. Eckhardt, Jacques Lefebvre Dec 1999

Langmuir Monolayers As Disordered Solids: Disorder And Elastic Fluctuations In Mesophases , Tadeusz Luty, Craig J. Eckhardt, Jacques Lefebvre

Craig J. Eckhardt Publications

Ordering in Langmuir monolayer mesophases is examined using an approach based on the elastic theory of crystals. Molecular tails are modeled as ‘‘defects’’ grafted onto a two-dimensional elastic medium and are characterized by elastic dipoles. It is assumed that disorder in the parent, LS, phase is due to competition between local (within a domain) and global (hexagonal arrangement of domains) structure. By treating the LS phase as a mixture of rectangular and/or oblique domains (rectangular and/or oblique defects within the two-dimensional elastic medium), density fluctuations due to elastic interactions between domains are analyzed. The correlation function for the ...


Noncommutative Computer Algebra In The Control Of Singularly Perturbed Dynamical Systems, J. W. Helton, F. Dell Kronewitter, Mark Stankus Dec 1999

Noncommutative Computer Algebra In The Control Of Singularly Perturbed Dynamical Systems, J. W. Helton, F. Dell Kronewitter, Mark Stankus

Mathematics

Most algebraic calculations which one sees in linear systems theory, for example in IEEE TAC, involve block matrices and so are highly noncommutative. Thus conventional commutative computer algebra packages, as in Mathematica and Maple, do not address them. Here we investigate the usefulness of noncommutative computer algebra in a particular area of control theory-singularly perturbed dynamic systems-where working with the noncommutative polynomials involved is especially tedious. Our conclusion is that they have considerable potential for helping practitioners with such computations. For example, the methods introduced here take the most standard textbook singular perturbation calculation, [KK086], one step further than had ...