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A Class Of Non-Binary Matroids With Many Binary Minors, Allan D. Mills, James G. Oxley Sep 1999

A Class Of Non-Binary Matroids With Many Binary Minors, Allan D. Mills, James G. Oxley

Faculty Publications

It is a well-known result of Tutte, A homotopy theorem for matroids, I, II, Trans. Amer. Math. Soc. 88 (1958) 144-174. that U2,4 is the only non-binary matroid M such that, for every element e, both M\e and M/e are binary. Oxley generalized this result by characterizing the non-binary matroids M such that, for every element e of M, the deletion M\e or the contraction M/e is binary. We characterize those non-binary matroids M such that, for all elements e and f, at least two of M\e, f; M\e/f; M/e\f; and M/e, f are binary. © 1999 Elsevier Science B.V. …

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Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls Sep 1999

Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls

Faculty Publications

No abstract provided.

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Evaluation Of The Use Of Optical Fiber Thermometers For Thermal Control Of The Quench Module Insert, Matthew R. Jones, Jeffery T. Farmer, Shawn P. Breeding Sep 1999

Evaluation Of The Use Of Optical Fiber Thermometers For Thermal Control Of The Quench Module Insert, Matthew R. Jones, Jeffery T. Farmer, Shawn P. Breeding

Faculty Publications

Issues regarding the use of optical fiber thermometers to control heater settings in a microgravity vacuum furnace are addressed. It is desirable to use these probes in environments such as the International Space Station, because they can be operated without re-calibration for extended periods. However, the analysis presented in this paper shows that temperature readings obtained using optical fiber thermometers can be corrupted by emissions from the fiber when extended portions of the probe are exposed to elevated temperatures.

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Patient And Care Giver Perceptions Of Cancer Pain Control, Patricia Rushton, Sherry Brown Sep 1999

Patient And Care Giver Perceptions Of Cancer Pain Control, Patricia Rushton, Sherry Brown

Faculty Publications

PURPOSE: This study measured the perceptions of Utah cancer patients and cargivers concerning knowledge about and adequacy of pharmacologic cancer pain control. METHODS: A descriptive survey was used. Questionnaires were sent to cancer patients and caregivers surveying their knowledge about and perceptions of the adequacy of pharmacologic cancer pain control. RESULTS: The study had a 52% response rate (259 of 500). Eighty five percent (219 of 259) of the respondents stated they had no cancer pain. CLINICAL IMPLICATIONS: Cancer literature indicated that much cancer pain is not effectively controlled. The majority of the respondents of this study reported no pain. …

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The World Of Courtroom Technology, Fredric I. Lederer Sep 1999

The World Of Courtroom Technology, Fredric I. Lederer

Faculty Publications

No abstract provided.

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Training Providers: Working With Lesbian Clients., Laurie A. Drabble Sep 1999

Training Providers: Working With Lesbian Clients., Laurie A. Drabble

Faculty Publications

No abstract provided.

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Dust Formation Above Cool Magnetic Spots In Evolved Stars, Noam Soker, Geoffrey C. Clayton Aug 1999

Dust Formation Above Cool Magnetic Spots In Evolved Stars, Noam Soker, Geoffrey C. Clayton

Faculty Publications

We examine the structure of cool magnetic spots in the photospheres of evolved stars, specifically asymptotic giant branch (AGB) stars and R Coronae Borealis (RCB) stars. We find that the photosphere of a cool magnetic spot will be above the surrounding photosphere of AGB stars, which is the opposite of the situation in the Sun. This results from the behaviour of the opacity, which increases with decreasing temperature, which again is the opposite of the behaviour of the opacity near the effective temperature of the Sun. We analyse the formation of dust above the cool magnetic spots, and suggest that …

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Mathematical Modelling Of Extracellular Matrix Dynamics Using Discrete Cells: Fiber Orientation And Tissue Regeneration, J. C. Dallon, J. A. Sherratt, P. K. Maini Aug 1999

Mathematical Modelling Of Extracellular Matrix Dynamics Using Discrete Cells: Fiber Orientation And Tissue Regeneration, J. C. Dallon, J. A. Sherratt, P. K. Maini

Faculty Publications

Matrix orientation plays a crucial role in determining the severity of scar tissue after dermal wounding. We present a model framework which allows us to examine the interaction of many of the factors involved in orientation and alignment. Within this framework, cells are considered as discrete objects, while the matrix is modeled as a continuum. Using numerical simulations, we investigate the effect on alignment of changing cell properties and of varying cell interactions with collagen and fibrin.

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Wetlands: A Potentially Significant Source Of Atmospheric Methyl Bromide And Methyl Chloride, Ruth K. Varner, Patrick M. Crill, Robert W. Talbot Aug 1999

Wetlands: A Potentially Significant Source Of Atmospheric Methyl Bromide And Methyl Chloride, Ruth K. Varner, Patrick M. Crill, Robert W. Talbot

Faculty Publications

Tropospheric methyl bromide (CH3Br) and methyl chloride (CH3Cl) are significant sources of ozone (O3) destroying halogens to the stratosphere. Their O3 depletion potential (ODP) can be determined from atmospheric lifetimes and therefore their atmospheric budgets, both of which are out of balance with known sink terms larger than identified sources. We have discovered a new source of CH3Br and CH3Cl emissions to the atmosphere at two wetland sites in the Northeastern United States. We have reason to believe that these compounds are biologically produced in situ. Our measurements indicate that the global annual flux of CH3Br and CH3Cl from wetlands …

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Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich Aug 1999

Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich

Faculty Publications

No abstract provided.

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The Spectrum Of Grb 930131 ("Superbowl Burst") From 20 Kev To 200 Mev, Volker Bromm, Bradley E. Schaefer Aug 1999

The Spectrum Of Grb 930131 ("Superbowl Burst") From 20 Kev To 200 Mev, Volker Bromm, Bradley E. Schaefer

Faculty Publications

We have constructed a broadband spectrum for GRB 930131 (the "Superbowl Burst"), ranging from 20 keV to 200 MeV, by combining spectral information from the Gamma Ray Observatory's BATSE, COMPTEL, and EGRET instruments. We present general methods for combining spectra from different time intervals obtained by the same instrument as well as for combining spectra from the same time interval taken by different instruments. The resulting spectrum is remarkably flat (in vFv-space) up to high energies. We find that the spectral shape can be successfully fitted by the shocked synchrotron emission model of Tavani. We present evidence that the flatness …

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Polymerization-Induced Phase Separation, J.C. Lee Aug 1999

Polymerization-Induced Phase Separation, J.C. Lee

Faculty Publications

A molecular dynamics simulation is performed to study the kinetics of microphase separation in a polymer-dispersed-liquid-crystal forming process. An equimolar mixture of monomers and liquid crystal molecules are thermalized in a well mixed state. The monomers are then polymerized at the same temperature. The end product is a spanning gel with liquid crystal molecules aggregating in droplets here and there. The peak position of the equal-time structure function suggests that the growth of the droplets may be described with t-0.23. The small growth exponent is just one of several features which may be attributed to the growing elastic …

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Nonlinear Robust Missile Autopilot Design Using Successive Galerkin Approximation, Timothy Mclain, Randal W. Beard Aug 1999

Nonlinear Robust Missile Autopilot Design Using Successive Galerkin Approximation, Timothy Mclain, Randal W. Beard

Faculty Publications

The application of a new nonlinear robust control strategy to the design of missile autopilots is presented. The control approach described and demonstrated here is based upon the numerical solution of the Hamilton-Jacobi-Isaacs equation by Successive Galerkin Approximation. Using this approach, feedback controllers are computed by an iterative application of a numerical Galerkin-type PDE solver. Application of this approach to the design of a pitch-axis autopilot for a missile having uncertain pitch moment and lift force is described.

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Theoretical And Practical Requirements For A System Of Pre-Design Analysis, Andrew S. Gibbons, Jon S. Nelson, Robert E. Richards Aug 1999

Theoretical And Practical Requirements For A System Of Pre-Design Analysis, Andrew S. Gibbons, Jon S. Nelson, Robert E. Richards

Faculty Publications

This research is aimed at bridging the worlds of simulation design as practiced by computer scientists and systems engineers and instructional design as practiced by a multitude of corporate, government, and military instructional designers, most of whom lack formal schooling in the techniques of either area.

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Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng Jul 1999

Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

This work focuses on improving the Hopfield network for solving optimization problems. Although much work has been done in this area, the performance of the Hopfield network is still not satisfactory in terms of valid convergence and quality of solutions. We address this issue in this work by combing a new activation function (EBA) and a new relaxation procedure (CR) in order to improve the performance of the Hopfield network. Each of EBA and CR has been individually demonstrated capable of substantially improving the performance. The combined approach has been evaluated through 20,000 simulations based on 200 randomly generated city …

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An Ellam Scheme For Advection-Diffusion Equations In Two Dimensions, Hong Wang, Helge K. Dahle, Richard E. Ewing, Magne S. Espedal, Robert Sharpley, Shushuang Man Jul 1999

An Ellam Scheme For Advection-Diffusion Equations In Two Dimensions, Hong Wang, Helge K. Dahle, Richard E. Ewing, Magne S. Espedal, Robert Sharpley, Shushuang Man

Faculty Publications

We develop an Eulerian--Lagrangian localized adjoint method (ELLAM) to solve two-dimensional advection-diffusion equations with all combinations of inflow and outflow Dirichlet, Neumann, and flux boundary conditions. The ELLAM formalism provides a systematic framework for implementation of general boundary conditions, leading to mass-conservative numerical schemes. The computational advantages of the ELLAM approximation have been demonstrated for a number of one-dimensional transport systems; practical implementations of ELLAM schemes in multiple spatial dimensions that require careful algorithm development are discussed in detail in this paper. Extensive numerical results are presented to compare the ELLAM scheme with many widely used numerical methods and to …

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Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson Jul 1999

Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Neural network and machine learning algorithms often have parameters that must be tuned for good performance on a particular task. Leave-one-out cross-validation (LCV) accuracy is often used to measure the fitness of a set of parameter values. However, small changes in parameters often have no effect on LCV accuracy. Many learning algorithms can measure the confidence of a classification decision, but often confidence alone is an inappropriate measure of fitness. This paper proposes a combined measure of Cross- Validation and Confidence (CVC) for obtaining a continuous measure of fitness for sets of parameters in learning algorithms. This paper also proposes …

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Cross Validation And Mlp Architecture Selection, Timothy L. Andersen, Tony R. Martinez Jul 1999

Cross Validation And Mlp Architecture Selection, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

The performance of cross validation (CV) based MLP architecture selection is examined using 14 real world problem domains. When testing many different network architectures the results show that CV is only slightly more likely than random to select the optimal network architecture, and that the strategy of using the simplest available network architecture performs better than CV in this case. Experimental evidence suggests several reasons for the poor performance of CV. In addition, three general strategies which lead to significant increase in the performance of CV are proposed. While this paper focuses on using CV to select the optimal MLP …

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The Little Neuron That Could, Timothy L. Andersen, Tony R. Martinez Jul 1999

The Little Neuron That Could, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

SLPs (single layer perceptrons) oflen exhibit reasonable generalization performance on many problems of interest. However, due to the well known limitations of SLPs very little effort has been made to improve their performance. This paper proposes a method for improving the performance of SLPs called "wagging" (weight averaging). This method involves training several different SLPs on the same training data, and then averaging their weights to obtain a single SLP. The performance of the wagged SLP is compared with other more complex learning algorithms (bp, c4.5, ibl, MML, etc) on 15 data sets from real world problem domains. Surprisingly, the …

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A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

A relaxation network model that includes higher order weight connections is introduced. To demonstrate its utility, the model is applied to the speech recognition domain. Traditional speech recognition systems typically consider only that context preceding the word to be recognized. However, intuition suggests that considering both preceding context as well as following context should improve recognition accuracy. The work described here tests this hypothesis by applying the higher order relaxation network to consider both precedes and follows context in speech recognition. The results demonstrate both the general utility of the higher order relaxation network as well as its improvement over …

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The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

Constraint satisfaction networks contain nodes that receive weighted evidence from external sources and/or other nodes. A relaxation process allows the activation of nodes to affect neighboring nodes, which in turn can affect their neighbors, allowing information to travel through a network. When doing discrete updates (as in a software implementation of a relaxation network), a goal net or goal activation can be computed in response to the net input into a node, and a relaxation rate can then be used to determine how fast the node moves from its current value to its goal value. An open question was whether …

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Seeking Causal Explanations In Social Epidemiology, Jay S. Kaufman, Richard S. Cooper Jul 1999

Seeking Causal Explanations In Social Epidemiology, Jay S. Kaufman, Richard S. Cooper

Faculty Publications

Social factors are associated with a wide variety of health outcomes. Social epidemiology has successfully used the traditional methods of surveillance and description to establish consistent relations between social factors and health status. Epidemiology as an etiologic science, however, has been largely ineffective in moving toward causal explanations for these observed patterns. Using the counterfactual approach to causal inference, the authors describe several fundamental problems that often arise when researchers seek to infer explanatory mechanisms from data on social factors. Contrasts that form standard causal effect estimates require implicit unobserved (counterfactual) quantities, because observational data provide only one exposure state …

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Is There An Absence Of Theory In Social Epidemiology? The Authors Respond To Muntaner, Richard S. Cooper, Jay S. Kaufman Jul 1999

Is There An Absence Of Theory In Social Epidemiology? The Authors Respond To Muntaner, Richard S. Cooper, Jay S. Kaufman

Faculty Publications

No abstract provided.

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The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth Jul 1999

The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth

Faculty Publications

Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will …

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Major Step Forward: Proposed Uniform Mediation Act Goes Public For Comments, Richard C. Reuben, Nancy H. Rogers Jul 1999

Major Step Forward: Proposed Uniform Mediation Act Goes Public For Comments, Richard C. Reuben, Nancy H. Rogers

Faculty Publications

The move toward a simplified and uniform law for mediation takes an important step forward this summer, with the release of the first integrated draft of the proposed Uniform Mediation Act. The act is being drafted by cooperating committees of the American Bar Association Section of Dispute Resolution and the National Conference of Commissioners on Uniform State Laws. If enacted and adopted uniformly, it would replace the hundreds of pages of complex and often conflicting statutes across the country with a few short pages of simple, accessible, and helpful rules.

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Defending Substantial Assistance: An Old Prosecutor's Meditation On Singleton, Sealed Case, And The Maxfield-Kramer Report, Frank O. Bowman Iii Jul 1999

Defending Substantial Assistance: An Old Prosecutor's Meditation On Singleton, Sealed Case, And The Maxfield-Kramer Report, Frank O. Bowman Iii

Faculty Publications

This essay begins with a brief analysis of the panel and en banc opinions in Sealed Case and Singleton, and then turns to the more arresting question of whether the panel decisions were transitory aberrations or something more. Particularly if one considers Singleton and Sealed Case together with the Sentencing Commission's staff report on substantial assistance practice (the “Maxfield - Kramer Report”), it is difficult to escape the conclusion that unease with the current substantial assistance regime is growing. Unlike many observers, I view §5K1.1 as a very good thing, an invaluable prosecutorial tool against group criminality, but a tool …

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Departing Is Such Sweet Sorrow: A Year Of Judicial Revolt On "Substantial Assistance" Departures Follows A Decade Of Prosecutorial Indiscipline (Prosecution Law Symposium), Frank O. Bowman Iii Jul 1999

Departing Is Such Sweet Sorrow: A Year Of Judicial Revolt On "Substantial Assistance" Departures Follows A Decade Of Prosecutorial Indiscipline (Prosecution Law Symposium), Frank O. Bowman Iii

Faculty Publications

the first section of this essay is devoted to demonstrating the courts' errors. Nonetheless, considered together, these opinions are perhaps an understandable reflection of judicial unease with an important component of the federal sentencing system — the longstanding, but increasingly common, practice of making deals with criminal defendants to reduce their sentences in return for testimony against their accomplices. This Article's second section will consider the most common criticisms of the system of bargaining for testimony under the United States Sentencing Guidelines (the Guidelines) to determine whether Singleton and Sealed Case may be good policy even if they are bad …

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Successive Causes And The Enigma Of Duplicated Harm, David A. Fischer Jul 1999

Successive Causes And The Enigma Of Duplicated Harm, David A. Fischer

Faculty Publications

Some of the most intriguing brain teasers in tort law involve the valuation of damages for harm arising from wrongfully inflicted injury to person or property. Consider the following example: A wrongdoer shoots and instantly kills a person in the path of an avalanche that would have killed the person a few seconds later. The person's survivors bring a wrongful death action against the shooter, seeking compensation for the loss of support they would have received from the decedent if she had lived. Should the court require the shooter to pay for loss of support beyond the time that the …

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Nautical Namesakes Of A.C. Van Raalte, Geoffrey D. Reynolds Jul 1999

Nautical Namesakes Of A.C. Van Raalte, Geoffrey D. Reynolds

Faculty Publications

Maritime Namesakes of A.C. Van Raalte is an article that concerns the history of the great lakes ships that bore his name for over eighty years.

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Die Altenglischen Glossen Zu Aldhelms "De Laudibus Virginitatis" In Der Handschrift Bl, Royal 6 B. Vii., Scott Gwara Jul 1999

Die Altenglischen Glossen Zu Aldhelms "De Laudibus Virginitatis" In Der Handschrift Bl, Royal 6 B. Vii., Scott Gwara

Faculty Publications

No abstract provided.

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