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Caudate Infarcts, Louis R. Caplan, Edward Feldmann, Jeremy D. Schmahmann, Carlos S. Kase, Phillip B. Gorelick, Daniel B. Hier, Cathy Helgason, George Baquis, John P. Greenberg Jan 1990

Caudate Infarcts, Louis R. Caplan, Edward Feldmann, Jeremy D. Schmahmann, Carlos S. Kase, Phillip B. Gorelick, Daniel B. Hier, Cathy Helgason, George Baquis, John P. Greenberg

Chemistry Faculty Research & Creative Works

Eighteen Patients Had Caudate Nucleus Infarcts (10 Left-Sided; 8 Right-Sided). Infarcts Extended into the Anterior Limb of the Internal Capsule in 9 Patients, and Also the Anterior Putamen in 5 Patients. Thirteen Patients Had Motor Signs, Most Often a Slight Transient Hemiparesis. Dysarthria Was Common (11 Patients). Cognitive and Behavioral Abnormalities Were Frequent, and Included Abulia (10 Patients), Agitation and Hyperactivity (7 Patients), Contralateral Neglect (3 Patients, All Right Caudate), and Language Abnormalities (2 Patients, Both Left Caudate). the Majority of Patients Had Risk Factors for Penetrating Artery Disease. Branch Occlusion of Heubner's Artery, or Perforators from the Proximal Anterior …


Highland: A Graph-Based Parallel Processing Environment For Heterogeneous Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer Jan 1990

Highland: A Graph-Based Parallel Processing Environment For Heterogeneous Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer

Computer Science Faculty Research & Creative Works

No abstract provided.


Distributed Evaluation Of An Iterative Function For All Object Pairs On A Simd Hypercube, Fikret Erçal Jan 1990

Distributed Evaluation Of An Iterative Function For All Object Pairs On A Simd Hypercube, Fikret Erçal

Computer Science Faculty Research & Creative Works

An efficient distributed algorithm for evaluating an iterative function on all pairwise combinations of C objects on an SIMD hypercube is presented. The algorithm achieves uniform load distribution and minimal, completely local interprocessor communication.


Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game Jan 1990

Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game

Computer Science Theses & Dissertations

The High-Performance Computing Initiative from the White House Office of Science and Technology Policy has defined 20 major challenges in science and engineering which are dependent on the solutions to a number of high-performance computing problems. One of the major areas of focus of this initiative is the development of gigabit rate networks to be used in environments such as the space station or a National Research and Educational Network (NREN).

The strategy here is to use existing network designs as building blocks for achieving higher rates, with the ultimate goal being a gigabit rate network. Two strategies which contribute …


High-Level Microprogramming: An Optimising C Compiler For A Processing Element Of A Cad Accelerator, Paul Kenyon, Prathima Agrawal, Sharad C. Seth Jan 1990

High-Level Microprogramming: An Optimising C Compiler For A Processing Element Of A Cad Accelerator, Paul Kenyon, Prathima Agrawal, Sharad C. Seth

School of Computing: Faculty Publications

The development of a high-level language compiler for a micro-programmable processing element (PE) in the MARS multicomputer is described. MARS, an MIMD message passing machine, was designed to speed up VLSI CAD and similar other non-numerical applications. The need for sup port of a high-level language at the PE level of a multicomputer is considered, and the choice of C as an appropriate programming language is justified. Special features found in VLSI processors are examined along with compiler support for them.

Conventional re-targetable compiler techniques are shown to be inadequate for the highly concurrent micro-programmable PE. These techniques must be …


A Notch-Strengthening Effect In Fresh-Water Ice, Wilfrid A. Nixon, Erland M. Schulson Jan 1990

A Notch-Strengthening Effect In Fresh-Water Ice, Wilfrid A. Nixon, Erland M. Schulson

Dartmouth Scholarship

Tensile tests have been performed onnotched and unnotched cylindrical samples of randomlyoriented polycrystalline ice of controlled grain-size (between2.2 and 7.3mm) at a loading rate of lOOPaS-l and at a temperature of -10 0c. In the notched samples, the notch-root diameter was 80% of the base diameter. Anotch-strengthening effect was observed in the large-grained ice, with fracture stresses being up to 50% higher than that for unnotched samples of the same grain-size. This notch-strengthening effect diminished as grain-size decreased, disappearing at a grain-size of "'3 mm. The notch-strengthening effect is explained in terms of the triaxial stress constraint at the notch …


An Underwater Science And Resource Database Management System And Proposed Applications To Marine Geographic Information Systems, Ivar Babb Jan 1990

An Underwater Science And Resource Database Management System And Proposed Applications To Marine Geographic Information Systems, Ivar Babb

Marine Affairs Theses and Major Papers

The National Undersea Research Program (NURP) is a federally-funded program that provides scientists with modern in situ technology that allows them to conduct research that goes beyond the constraints of traditional oceanographic methodology. NURP is comprised of five regional centers that administer underwater science, and through the principal investigators that are supported generate a vast quantity of diverse data. This data and information bank consists of the following: raw environmental data, logistical data, locational data, information about the scientists, video and still photograph documentation, and publication information. This paper describes the theory behind the implementation of a Database Management System …


An Evaluation Of Noaa's Role In Ocean Dumping Policy Implementation, Kenneth W. Barton Jan 1990

An Evaluation Of Noaa's Role In Ocean Dumping Policy Implementation, Kenneth W. Barton

Marine Affairs Theses and Major Papers

Dumping of wastes into the ocean has gone on for years especially in the New York Bight. The National Oceanic and Atmospheric Administration (NOAA) is mandated by Title II of the Ocean Dumping Act of 1972 to investigate the effects of ocean dumping on the marine environment. However, there is a perception within Congress, the public and other agencies that NOAA is not meeting it's responsibilities with regard to ocean dumping research. The effectiveness of NOAA's ocean dumping policies and programs and the difficulties in implementation experienced by the agency are evaluated by applying George Edwards' theory of policy implementation. …


Maritime Boundaries Of India - A Case Study, Piyali Talukdar Jan 1990

Maritime Boundaries Of India - A Case Study, Piyali Talukdar

Marine Affairs Theses and Major Papers

This study examines the present status of the maritime boundaries of India in the context of applicable international laws related to boundary definition. As a developing nation with a long coastline and large Exclusive Economic Zone, it is important for India to define its boundary limits for better utilization and management of its marine resources. India has maritime boundaries with seven different nations; the geographical setting, political relationships and economic importances are different in each case, making each situation unique. Since appreciation of factors such as geographical, geophysical, resource potentials, etc. can help to realize the shape of the present …


The Effect Of Industrial Development On The Sediment Contamination Of Apponaug Cove, A Historical Analysis, Marina Havan-Orumieh Jan 1990

The Effect Of Industrial Development On The Sediment Contamination Of Apponaug Cove, A Historical Analysis, Marina Havan-Orumieh

Marine Affairs Theses and Major Papers

Sediment cores have long been used to formulate the chronology of environmental contamination. This paper will investigate the utility of sediment cores in determining the chronology of trace metal contamination in Apponaug Cove, Rhode Island. A meter-long sediment core taken from the Cove was analyzed for chromium, copper, lead, zinc and nickel as well as organic pollutants coprostanol, polyaromatic hydrocarbons, benzotriazole and clorobenzotriazole. The core represents a close to 200 year record of sediments in Apponaug Cove. The cultural/economic changes in the Watershed in addition to environmental laws composed in the State and Federal levels which may have correlated with …


University Of Texas At Tyler Catalog, 1990-1992, University Of Texas At Tyler Jan 1990

University Of Texas At Tyler Catalog, 1990-1992, University Of Texas At Tyler

Catalogs

This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. In addition, no permission is required from the rights-holder(s) for educational uses. For other uses, you need to obtain permission from the rights-holder(s).


Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf Jan 1990

Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf

Chemistry Faculty Research & Creative Works

We Determined the Prevalence of Dementia in 927 Patients with Acute Ischemic Stroke Aged ≥60 Years in the Stroke Data Bank Cohort based on the Examining Neurologist's Best Judgment Diagnostic Agreement among Examiners Was 68% (K=0.34). of 726 Testable Patients, 116 (16%) Were Demented. Prevalence of Dementia Was Related to Age But Not to Sex, Race, Handedness, Educational Level, or Employment Status Before the Stroke. Previous Stroke and Previous Myocardial Infarction Were Related to Prevalence of Dementia Although Hypertension, Diabetes Mellitus, Atrial Fibrillation, and Previous Use of Antithrombotic Drugs Were Not Prevalence of Dementia Was Most Frequent in Patients with …


Experimentation With Large-Grained Parallelism Using Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer Jan 1990

Experimentation With Large-Grained Parallelism Using Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer

Computer Science Faculty Research & Creative Works

HIGHLAND, a distributed-memory parallel processing environment for heterogeneous local area networks, has been developed. Designed as both a teaching and a research tool, its purpose is to provide an effective mechanism by which a number of networked UNIX workstations, dissimilar in both vendor and performance, can be directly manipulated as a single, unified, multiprocessing system. Utilizing the MIT X-windows environment, HIGHLAND supports a highly interactive graphical interface through which a programmer can create, modify, and control complex systems of communicating processes


State-Selective Capture In Collisions Between Ions And Ground- And Excited-State Alkali-Metal Atoms, J. Pascale, Ronald E. Olson, C. O. Reinhold Jan 1990

State-Selective Capture In Collisions Between Ions And Ground- And Excited-State Alkali-Metal Atoms, J. Pascale, Ronald E. Olson, C. O. Reinhold

Physics Faculty Research & Creative Works

Total cross sections for state-selective electron capture in collisions between ions and alkali-metal atoms have been calculated by means of a three-body classical-trajectory Monte Carlo (CTMC) method using model potentials to describe the electron ionic-core interactions. Calculations have been performed for Na+-Na(28d) collisions and for N5+ and Ar8+-Cs(6s) collisions. The collision velocity range corresponds to 0.5vp/ve2, where vp is the projectile velocity in the laboratory frame and ve is the initial orbital velocity of the electron bound to the alkali-metal core. In the case of Na++Na(28d) collisions, calculations of the final n,l,m distributions …


Binary Nucleation Of Ethanol And Water, John L. Schmitt, J. Whitten, G. W. Adams, R. A. Zalabsky Jan 1990

Binary Nucleation Of Ethanol And Water, John L. Schmitt, J. Whitten, G. W. Adams, R. A. Zalabsky

Physics Faculty Research & Creative Works

The authors have used a fast expansion cloud chamber to measure binary homogeneous nucleation rates in several ethanol-water mixtures as a function of temperature, ethanol and water activities and nucleation rate. Data (ethanol and water activities) are presented for a range in nucleation rate from 10 3 to 105 drops/cm3 s from 263 to 293 K for mixtures having mole ratios (ethanol/water) of 10, 4, 0.1, 0.01, and 0.001. A comparison of the extensive data set to other data in the literature shows good agreement. We find current theory, as expected, is unable to accurately predict the data at low …


Rotational Effects In The Continuous Vacuum-Ultraviolet Fluorescence Spectrum Of H2 Associated With Spontaneous Dissociation, H. Schmoranzer, T. Noll, E. Roueff, H. Abgrall, Ronald James Bieniek Jan 1990

Rotational Effects In The Continuous Vacuum-Ultraviolet Fluorescence Spectrum Of H2 Associated With Spontaneous Dissociation, H. Schmoranzer, T. Noll, E. Roueff, H. Abgrall, Ronald James Bieniek

Physics Faculty Research & Creative Works

The effects of rotational-vibrational interaction, and of rotational coupling between the B 2p u+1 and C 2p u1 electronic states, on the B X fluorescence continuum of H2 associated with spontaneous dissociation were investigated spectroscopically using monochromatized synchrotron radiation for selective excitation of rovibronic states. The rotational shifts and perturbations in the modulated continua intensities observed agree well with close-coupling and Jeffreys-Wentzel-Kromers-Brillouin (JWKB) calculations also performed and are explained in terms of nonadiabatic coupling effects and rainbow-interference structures. A straightforward experimental technique is described to detect mixed electronic states. © 1990 The American Physical Society.


Digital Image Processing Using Mathematical Morphology, Andrew Mehnert Jan 1990

Digital Image Processing Using Mathematical Morphology, Andrew Mehnert

Theses : Honours

This dissertation is a natural extension of my undergraduate research project entitled, "Digital Image Processing”. Whilst my undergraduate project dealt with a number of classical digital image filtering techniques such as spatial convolution and frequency domain filtering via the Fourier transform, this dissertation focuses on an alternative approach employing Mathematical Morphology. In contrast to classical filtering techniques, which often geometrically distort the original image, morphological operations, used sensibly, essentially preserve shape and geometry. Mathematical morphology therefore lends itself to image processing applications requiring the identification of objects and object features within an image. Herein basic morphological operations are developed, firstly …


Data Security: The Securing Of Computer Installations And Data Sets, Willy B. Kuehnle Jan 1990

Data Security: The Securing Of Computer Installations And Data Sets, Willy B. Kuehnle

Theses

No abstract provided.


Earth Day 2020: Will We Have A Healthier Environment?, George T. Frampton, Jr., University Of Colorado Boulder. Natural Resources Law Center Jan 1990

Earth Day 2020: Will We Have A Healthier Environment?, George T. Frampton, Jr., University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

10 leaves ; 28 cm


From Basin To "Hydrocommons": Integrated Water Management Without Regional Governance, Gary D. Weatherford, University Of Colorado Boulder. Natural Resources Law Center Jan 1990

From Basin To "Hydrocommons": Integrated Water Management Without Regional Governance, Gary D. Weatherford, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

22 p. ; 28 cm


Water And The Cities Of The Southwest, John A. Folk-Williams, University Of Colorado Boulder. Natural Resources Law Center Jan 1990

Water And The Cities Of The Southwest, John A. Folk-Williams, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

13 p. ; 28 cm


Water Rights Decisions In The Western States: Upgrading The System For The 21st Century, Steven J. Shupe, University Of Colorado Boulder. Natural Resources Law Center Jan 1990

Water Rights Decisions In The Western States: Upgrading The System For The 21st Century, Steven J. Shupe, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

18 p. ; 28 cm


Phytoplankton Dynamics In Three Rocky Mountain Lakes, Colorado, U.S.A., Diane M. Mcknight, Richard L. Smith, J. Platt Bradbury, Jill S. Baron, Sarah Spaulding Jan 1990

Phytoplankton Dynamics In Three Rocky Mountain Lakes, Colorado, U.S.A., Diane M. Mcknight, Richard L. Smith, J. Platt Bradbury, Jill S. Baron, Sarah Spaulding

United States Geological Survey: Staff Publications

In 1984 and 1985 seasonal changes in phytoplankton were studied in a system of three lakes in Loch Vale, Rocky Mountain National Park, Colorado. Three periods were evident: (1) A spring bloom, during snowmelt, of the planktonic diatom Asterionella Formosa, (2) a mid- summer period of minimal algal abundance, and (3) a fall bloom of the blue-green alga Oscillatoria limnetica. Seasonal phytoplankton dynamics in these lakes are controlled partially by the rapid flushing rate during snowmelt and the transport of phytoplankton from the highest lake to the lower lakes by the stream, Icy Brook. During snowmelt, the A. …


Crustal Strain Near The Big Bend Of The San Andreas Fault: Analysis Of The Los Padres-Tehachapi Trilateration Networks, California, Donna Eberhart-Phillips, Michael Lisowski, Mark D. Zoback Jan 1990

Crustal Strain Near The Big Bend Of The San Andreas Fault: Analysis Of The Los Padres-Tehachapi Trilateration Networks, California, Donna Eberhart-Phillips, Michael Lisowski, Mark D. Zoback

United States Geological Survey: Staff Publications

In the region of the Los Padres-Tehachapi geodetic network, the San Andreas fault (SAF) changes its orientation by over 30 ° from N40 °W, close to that predicted by plate motion for a transform boundary, to N73 °W. The strain orientation near the SAF is consistent with right-lateral shear along the fault, with maximum shear rate of 0.38 ± 0.01 μrad/yr at N63 °W. In contrast, away from the SAF the strain orientations on both sides of the fault are consistent with the plate motion direction, with maximum shear rate of 0.19 ± 0.01 μrad/yr at N44 °W. The strain …


Design Of A Dynamically Reconfigurable, Integrated, Parallel Vision System, Ashok K. Samal Jan 1990

Design Of A Dynamically Reconfigurable, Integrated, Parallel Vision System, Ashok K. Samal

School of Computing: Conference and Workshop Papers

Multiprocessors can be used to speed up the process of object recognition. Building a parallel vision system is a two step process: (a) design and implement parallel algorithms for individual operations, and (b) integrate them into a coherent system. So far the emphasis has been on the first step. The second step has not received enough attention. A framework for building a parallel vision system is presented here. The necessary and desirable features of such a system have been identified. An initial design which incorporates these features is also given.


An Experimental Study On Reject Ratio Prediction For Vlsl Circuits: Kokomo Revisited, Dharam Vir Das, Sharad C. Seth, Paul T. Wagner, John Anderson, Vishwani Agrawal Jan 1990

An Experimental Study On Reject Ratio Prediction For Vlsl Circuits: Kokomo Revisited, Dharam Vir Das, Sharad C. Seth, Paul T. Wagner, John Anderson, Vishwani Agrawal

School of Computing: Faculty Publications

Assuring product quality is becoming increasingly more important for the semiconductor chip manufacturers. The reject ratio (defect level) provides a simple and accurate measure of a product's quality. However, measuring the reject ratio of tested chips is often not feasible or accurate. Statistical techniques for reject ratio prediction provide a possible way out of this dilemma. In this paper, we report on an experiment to verify the accuracy of reject ratio predictions by the available approaches. The data collection effort includes instrumenting the wafer probe test to obtain chip failures as a function of applied vectors and running a fault …


Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng Jan 1990

Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng

Research Collection School Of Computing and Information Systems

A 2L-dimensional multiple phase-shift keyed (L×MPSK) signal set is obtained by forming the Cartesian product of L two-dimensional MPSK signal sets. A systematic approach to partitioning L×MPSK signal sets that is based on block coding is used. An encoder system approach is developed. It incorporates the design of a differential precoder, a systematic convolutional encoder, and a signal set mapper. Trellis-coded L×4PSK, L×8PSK, and L×16PSK modulation schemes are found for 1⩽L⩽4 and a variety of code rates and decoder complexities, many of which are fully transparent to discrete phase rotations of the signal set. The new codes achieve asymptotic coding …


Experimental Comparison Of Bidding And Drafting Load Sharing Protocols, Andrew Ross, Bruce M. Mcmillin Jan 1990

Experimental Comparison Of Bidding And Drafting Load Sharing Protocols, Andrew Ross, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

In recent years, a dramatic rise in the number of personal workstations interconnected via local area networks has occurred in the workplace. These can be organized as distributed computing systems. The combined computing power of these systems are often greater than mainframes of a decade ago, and usually less expensive. There is a growing interest in harnessing this often-underutilized power. Researchers are focusing their attention on remote execution of processes as one solution. An additional topic of research is to balance a workload among a series of computers. Remote execution is made possible because the distributed operating system provides migration …


Linda Implementations Using Monitors And Message Passing, Alan L. Leveton Jan 1990

Linda Implementations Using Monitors And Message Passing, Alan L. Leveton

UNF Graduate Theses and Dissertations

Linda is a new parallel programming language that is built around an interprocess communication model called generative communication that differs from previous models in specifying that shared data be added in tuple form to an environment called tuple space, where a tuple exists independently until some process chooses to use it. Interesting properties arise from the model, including space and time uncoupling as well as structured naming. We delineate the essential Linda operations, then discuss the properties of generative communication. We are particularly concerned with implementing Linda on top of two traditional parallel programming paradigms - process communication through globally …


Human-Machine Interface For Tactical Air Traffic Control Communications, Alan Mastin Jan 1990

Human-Machine Interface For Tactical Air Traffic Control Communications, Alan Mastin

UNF Graduate Theses and Dissertations

This thesis proposes the design for a prototype device that would be used by Air Traffic Controllers in the radar environment to input tactical Air Traffic Control (ATC) instructions to be sent to aircraft via the Mode S digital data link network. The purpose of the device is to reduce the time required to issue instructions and to eliminate misunderstandings that occur when instructions are issued over voice transmission frequencies. The purpose of this thesis was to develop the device in the most ergonomically suited manner based on the air traffic controller's communications requirements. Digital communications systems include both airborne …