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Nonrecursive Incremental Evaluation Of Datalog Queries, Guozhu Dong, Jianwen Su, Rodney Topor Jan 1995

Nonrecursive Incremental Evaluation Of Datalog Queries, Guozhu Dong, Jianwen Su, Rodney Topor

Kno.e.sis Publications

We consider the problem of repeatedly evaluating the same (computationally expensive) query to a database that is being updated between successive query requests. In this situation, it should be possible to use the difference between successive database states and the answer to the query in one state to reduce the cost of evaluating the query in the next state. We use nonrecursive Datalog (which are unions of conjunctive queries) to compute the differences, and call this process “incremental query evaluation using conjunctive queries”. After formalizing the notion of incremental query evaluation using conjunctive queries, we give an algorithm that constructs, …

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Error Control For Continuous Media And Multipoint Applications, Christos Papadopoulos, Guru Parulkar Jan 1995

Error Control For Continuous Media And Multipoint Applications, Christos Papadopoulos, Guru Parulkar

All Computer Science and Engineering Research

High-bandwidth multimedia applications pose new challenges to error control. These include the support of error control for Continuous Media (CM) streams and the scalable support of error control in multipoint applications where the number of participants is large. Current error control mechanisms provide no support for the above applications. In this report we present new error control mechanisms that provide the required support. Continuous media applications have strict timing requirements which greatly affect recovery. To support continuous media applications we have designed and implemented a point-to-point error control mechanism which features the following: (1) selective repeat retransmission, (2) conditional retransmission, …

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Some Relationships Between Sedimentary Trace Metal Concentrations And Freshwater Phytoplankton And Sedimentary Diatom Species Composition, Allan Hayes Vogel Jan 1995

Some Relationships Between Sedimentary Trace Metal Concentrations And Freshwater Phytoplankton And Sedimentary Diatom Species Composition, Allan Hayes Vogel

Dissertations and Theses

Sediments from 21 Oregon lakes were analyzed for seven metals (Fe, Mn, Zn, Cu, Co, Ni, V) in three forms (exchangeable, organic+sulfides, and oxyhydroxides+ oxides+ carbonates) using a sequential fractionation procedure. The summer epilimnetic filterable concentration of an eighth (Mo) was also determined. Sedimentary diatom remains and summer phytoplankton populations of the lakes were correlated with the 22 metal parameters and with conservative water chemistry parameters, estimators of lake productivity, and watershed geology. Both the sedimentary metals and the two populations of primary producers correlated best with the ecoregions of Omernik and Gallant (1986). A number of species possessed correlations …

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Syntheses Of Cross-Linking Agents, Molecular Modeling Of Oligonucleotides And Polypeptide-Ion Complexes, Michael J. Yunes Jan 1995

Syntheses Of Cross-Linking Agents, Molecular Modeling Of Oligonucleotides And Polypeptide-Ion Complexes, Michael J. Yunes

Honors Theses

Each section of this thesis will be subdivided into three parts encompassing all of the research in which I have been involved during the past three years. These will be referred to under the headings "Syntheses:' "Molecular Modeling," and "Cross-linking Efficiencies." Each of these subdivisions may have divisions within them when necessary in order to fully detail the research.

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Determination Of Hydroxyl Radical Production Rates In Natural Waters Using The Fluorometric Reagent P-Hydroxyphenylacetic Acid, Jason D. Hosmer Jan 1995

Determination Of Hydroxyl Radical Production Rates In Natural Waters Using The Fluorometric Reagent P-Hydroxyphenylacetic Acid, Jason D. Hosmer

Honors Theses

A means of determining hydroxyl radical production rates in natural waters through the formation of a directly detectable fluorescent product has been developed. A method similar to the enzyme mediated oxidation of phydroxyphenylacetic acid by hydrogen peroxide is used (Miller and Kester, 1988). Due to the high reactivity of hydroxyl radicals, and subsequently low steady state concentrations, direct detection is very difficult. In the past detection was achieved through the introduction of a probe, usually a substituted aromatic or alcohol, that decays away at an observable rate upon reaction with hydroxyl radicals. Detection limits and accuracy of such difference based …

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Alkaline Phosphatase Activity And Phosphorus Limitation In Marine Macroalgae From The Florida Keys And The Bahamas, Christine M. Urnezis Jan 1995

Alkaline Phosphatase Activity And Phosphorus Limitation In Marine Macroalgae From The Florida Keys And The Bahamas, Christine M. Urnezis

HCNSO Student Theses and Dissertations

Anthropogenic nutrient enrichment and coastal eutrophication are a primary threat to the biological integrity of coral reef ecosystems. Macroalgal blooms are one symptom of eutrophication and provide useful 'bioindicators' of the nutrient dynamics associated with the eutrophication process. This study used marine macroalgae to monitor physiological processes associated with eutrophication by comparing the degree of phosphorus (P) limitation in reef and nearshore environments of the highly developed Florida Keys with the relatively pristine Bahamas by measuring enzymatic alkaline phosphatase activity (APA), tissue composition, and water column nutrient concentrations [total nitrogen (TN) and total phosphorus (TP)]. Experimental nutrient enrichment studies were …

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A Taxonomy Of Workgroup Computing Applications, Warren Von Worley Jan 1995

A Taxonomy Of Workgroup Computing Applications, Warren Von Worley

CCAC Theses and Dissertations

The goal of workgroup computing is to help individuals and groups efficiently perform a wide range of functions on networked computer systems (Ellis, Gibbs, & Rein, 1991). Early workgroup computing tools were designed for limited functionality and group interaction (Craighill, 1992). Current workgroup computing applications do not allow enough control of group processes and they provide little correlation between various workgroup computing application areas (Rodden and Blair, 1991). An integrated common architecture may produce more effective workgroup computing applications. Integrating common support functions into a common framework will avoid duplication of these functions for each workgroup computing application (Pastor & …

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Reading The Rangeland: A Guide To The Arid Shrublands Of Western Australia, Don Burnside, Alec Holm, Alan Payne, Georgina Wilson Jan 1995

Reading The Rangeland: A Guide To The Arid Shrublands Of Western Australia, Don Burnside, Alec Holm, Alan Payne, Georgina Wilson

All other publications

Managing the rangelands is complex. Soils and vegetation can vary considerably over short distances in distinct or subtle ways. Separating climatic from management influences on the condition of the land has always been difficult. Whether we live on a sheep station, in a country town, in an Aboriginal community, a mining camp, or even if we only visit the Australian outback, it is vital that we understand and appreciate the unique character and management requirements of the rangelands. Learning to ‘read the rangeland’ has been a slow process, involving the knowledge and skills of pastoralists, Aboriginal people and scientists. This …

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Inversion Of A Soil Bidirectional Reflectance Model For Use With Vegetation Reflectance Models, Jeffrey L. Privette, Ranga B. Myneni, William J. Emery, Bernard Pinty Jan 1995

Inversion Of A Soil Bidirectional Reflectance Model For Use With Vegetation Reflectance Models, Jeffrey L. Privette, Ranga B. Myneni, William J. Emery, Bernard Pinty

United States National Aeronautics and Space Administration: Publications

The need for anisotropic soil reflectance modelling is assessed for different sampling and canopy conditions.

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Effects Of Longwall Mining On Hydrogeology, Leslie County, Kentucky Part 1: Pre-Mining Conditions, Shelley A. Minns, James A. Kipp, Daniel I. Carey, James S. Dinger, Lyle V. A. Sendlein Jan 1995

Effects Of Longwall Mining On Hydrogeology, Leslie County, Kentucky Part 1: Pre-Mining Conditions, Shelley A. Minns, James A. Kipp, Daniel I. Carey, James S. Dinger, Lyle V. A. Sendlein

Report of Investigations--KGS

An investigation of the hydrologic effects of longwall coal mining is in progress in the Eastern Kentucky Coal Field. The study area is located in a first-order watershed in southern Leslie County over Shamrock Coal Company's Beech Fork Mine (Edd Fork Basin on the Helton 7.5-minute quadrangle). Longwall panels approximately 700 feet wide are separated by three-entry gateways 200 feet wide. The mine is operating in the Fire Clay coal (Hazard No. 4); overburden thickness ranges from 300 to 1,000 feet. Mining in the watershed began in late summer 1993. Undermining of the instrumented panel (panel 7) is anticipated for …

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The Use Of The National Information Infrastructure And High Performance Computers In Industry, Geoffrey C. Fox, Wojtek Furmanski Jan 1995

The Use Of The National Information Infrastructure And High Performance Computers In Industry, Geoffrey C. Fox, Wojtek Furmanski

Northeast Parallel Architecture Center

We divide potential NII (National Information Infrastructure) services into five broad areas: Collaboration and televirtuality; InfoVISiON (Information, Video, Imagery, and Simulation on Demand), and digital libraries; commerce; metacomputing; WebTop productivity services. The latter denotes the broad suite of tools we expect to be offered on the Web in a general environment we term WebWindows. We review current and future World Wide Web technologies, which could underlie these services. In particular, we suggest an integration framework WebWork for High Performance (parallel and distributed) computing and the NII. We point out that pervasive WebWork and WebWindows technologies will enable, facilitate and substantially …

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High Performance Distributed Computing, Geoffrey C. Fox Jan 1995

High Performance Distributed Computing, Geoffrey C. Fox

Northeast Parallel Architecture Center

High Performance Distributed Computing (HPDC) is driven by the rapid advance of two related technologies -- those underlying computing and communications, respectively. These technology pushes are linked to application pulls, which vary from the use of a cluster of some 20 workstations simulating fluid flow around an aircraft, to the complex linkage of several hundred million advanced PCs around the globe to deliver and receive multimedia information. The review of base technologies and exemplar applications is followed by a brief discussion of software models for HPDC, which are illustrated by two extremes -- PVM and the conjectured future World Wide …

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Numerical Results For The Ground-State Interface In A Random Medium, Alan Middleton Jan 1995

Numerical Results For The Ground-State Interface In A Random Medium, Alan Middleton

Physics - All Scholarship

The problem of determining the ground state of a $d$-dimensional interface embedded in a $(d+1)$-dimensional random medium is treated numerically. Using a minimum-cut algorithm, the exact ground states can be found for a number of problems for which other numerical methods are inexact and slow. In particular, results are presented for the roughness exponents and ground-state energy fluctuations in a random bond Ising model. It is found that the roughness exponent $\zeta = 0.41 \pm 0.01, 0.22 \pm 0.01$, with the related energy exponent being $\theta = 0.84 \pm 0.03, 1.45 \pm 0.04$, in $d = 2, 3$, respectively. These …

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Studies On The Cyclization Of Cis-1,4-Dichloro-2-Butene With Sodium Dialkylmalonates, Hovis M. E. Imade Jan 1995

Studies On The Cyclization Of Cis-1,4-Dichloro-2-Butene With Sodium Dialkylmalonates, Hovis M. E. Imade

Master's Theses

No abstract provided.

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Molecular Fluorescence Spectroscopy In The Vicinity Of A Microstructure, P.T. Leung, Thomas F. George Jan 1995

Molecular Fluorescence Spectroscopy In The Vicinity Of A Microstructure, P.T. Leung, Thomas F. George

Physics Faculty Publications and Presentations

A brief review is presented on fluorescence spectroscopy of molecules in the vicinity of a microstructure, which could be a surface structure, clustered ions/atoms, a colloidal particle in a solution, or a tip in certain molecular probes. This structure can be viewed as microscopic, mesoscopic or macroscopic, depending on the specific environment in which the molecule is located. An overview is given for selected experimental and theoretical aspects of this phenomenon, emphasizing some of the previous modeling work of the authors. Discussion of possible future attempts to explore the phenomenon in more detail is presented at the end.

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Singularity Of Super-Brownian Local Time At A Point Catalyst, Donald A. Dawson, Klaus Fleischmann, Yi Li, Carl Mueller Jan 1995

Singularity Of Super-Brownian Local Time At A Point Catalyst, Donald A. Dawson, Klaus Fleischmann, Yi Li, Carl Mueller

Mathematics and Statistics Faculty Publications

No abstract provided.

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Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie Jan 1995

Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie

Theses : Honours

Each year approximately 20 million hectares of land become affected by increasing salinity. Salt tolerant plants are being used to rehabilitate salt affected areas. Plants use a variety of mechanisms to adapt to salt in their environments. Glycophytes tolerate low to moderate levels of salt while halophytes can tolerate very high salt levels. Many basic physiological attributes have been suggested as important components of a salt tolerant phenotype. These include, influx and/or efflux of ions across plasma membrane and the tonoplast, modification of membrane composition and synthesis of compatible solutes such as soluble carbohydrates, glycine betaines and proline. The project …

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Brokered Collaborative Infrastructure For Cscw, Chandrajit Bajaj, Peinan Zhang, Alok R. Chaturvedi Jan 1995

Brokered Collaborative Infrastructure For Cscw, Chandrajit Bajaj, Peinan Zhang, Alok R. Chaturvedi

Department of Computer Science Technical Reports

No abstract provided.

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Radon Reduction, Improvement Of Indoor Air Quality, And Energy Savings Through An Original Solar Ventilation System, Heather E. Rhoads Jan 1995

Radon Reduction, Improvement Of Indoor Air Quality, And Energy Savings Through An Original Solar Ventilation System, Heather E. Rhoads

Dissertations and Theses @ UNI

This study evaluated the improvement of indoor air quality and energy savings achieved, by an original solar ventilation system installed at test sites exhibiting elevated radon levels. Conventional residential energy conservation measures that limit air exchange rates between the indoors and outdoors have been shown to increase concentrations of radioactive radon decay products as well as other indoor air contaminants. Growing concern about radon lung cancer risks, carbon monoxide poisoning, and the "sick building syndrome" have increased demand for improved indoor air quality. Due to added heating and cooling loads, ventilation generally incurs substantial installation and operational costs. All commercially …

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Soil Information Sheets For Ravensthorpe And Part Of The Jerramungup Agricultural Areas, Tim D. Overheu, Landcare Western Australia. Jan 1995

Soil Information Sheets For Ravensthorpe And Part Of The Jerramungup Agricultural Areas, Tim D. Overheu, Landcare Western Australia.

Agriculture reports

The soil information sheets produced for the Ravensthorpe Land Conservation District provide an easy reference guide to the soils for part of the Jerramungup and Ravensthorpe agricultural areas, and provide land use and soil management recommendations. Soil data are shown on the front of the sheet, and land use and land management information is given on the back. The information should be used as a guide, and encourage the user to seek further information through the relevant people and organisations.

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A Field Investigation Of Planimetric Knickpoint Morphology From Rock-Bed Sections Of Niagara Escarpment Fluvial Systems (Ontario), Richard Stanley Pyrce Jan 1995

A Field Investigation Of Planimetric Knickpoint Morphology From Rock-Bed Sections Of Niagara Escarpment Fluvial Systems (Ontario), Richard Stanley Pyrce

Theses and Dissertations (Comprehensive)

This study was an initial attempt to understand the impact of parents, peers, the media, and sex education curricula on shaping adolescents' knowledge and attitudes about dating relationships and sexuality. In addition, participants' descriptions of what constitutes a "good" date and a "bad" date were investigated. One hundred participants (48 females, 52 males) aged thirteen to sixteen participated: half of the sample were early adolescents (13-14 years) and the other half were middle adolescents (15-16 years). All participants were asked to describe experienced or hypothetical "good" and "bad" dates. For "good" dates, respondents identified engaging in fun, recreational activities, whereas …

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A Portable Computer System For Recording Heart Sounds And Data Modeling Using A Backpropagation Neural Network, Erik Mark Hudson Jan 1995

A Portable Computer System For Recording Heart Sounds And Data Modeling Using A Backpropagation Neural Network, Erik Mark Hudson

UNF Graduate Theses and Dissertations

Cardiac auscultation is the primary tool used by cardiologists to diagnose heart problems. Although effective, auscultation is limited by the effectiveness of human hearing. Digital sound technology and the pattern classification ability of neural networks may offer improvements in this area. Digital sound technology is now widely available on personal computers in the form of sound cards. A good deal of research over the last fifteen years has shown that neural networks can excel in diagnostic problem solving. To date, most research involving cardiology and neural networks has focussed on ECG pattern classification. This thesis explores the prospects of recording …

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Pollution Prevention Implementation Plan For Vehicle Maintenance, Iowa Small Business Development Centers, Iowa Waste Reduction Center Jan 1995

Pollution Prevention Implementation Plan For Vehicle Maintenance, Iowa Small Business Development Centers, Iowa Waste Reduction Center

Iowa Waste Reduction Center Book Gallery

The Pollution Prevention Implementation Plan for Vehicle Maintenance was prepared as part of the Iowa Pollution Prevention Initiative (IPPI) pilot project. IPPI demonstrated the team approach to small business pollution prevention technical assistance through integration of existing Iowa Small Business Development Center and Iowa Waste Reduction Center services. This cooperative effort was designed to help small businesses learn about and implement pollution prevention through recognition of pollution prevention options, comparison of costs and benefits, and evaluation of financing options. The Pollution Prevention Implementation Plan (PPIP) for Vehicle Maintenance provides: • An overview of pollution prevention options, • A review of …

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Pollution Prevention Implementation Plan For Printing Industries, Iowa Small Business Development Centers, Iowa Waste Reduction Center Jan 1995

Pollution Prevention Implementation Plan For Printing Industries, Iowa Small Business Development Centers, Iowa Waste Reduction Center

Iowa Waste Reduction Center Book Gallery

The Pollution Prevention Implementation Plan for Printers was prepared as part of the Iowa Pollution Prevention Initiative (IPPI) pilot project. IPPI demonstrated the team approach to small business pollution prevention technical assistance through integration of existing Iowa Small Business Development Center and Iowa Waste Reduction Center services. This cooperative effort was designed to help small businesses learn about and implement pollution prevention through recognition of pollution prevention options, comparison of costs and benefits, and evaluation of financing options. The Pollution Prevention Implementation Plan (PPIP) for Printers provides: • An overview of pollution prevention options, • A review of the costs …

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Pollution Prevention Implementation Plan For Metal Manufacturers, Iowa Small Business Development Centers, Iowa Waste Reduction Center Jan 1995

Pollution Prevention Implementation Plan For Metal Manufacturers, Iowa Small Business Development Centers, Iowa Waste Reduction Center

Iowa Waste Reduction Center Book Gallery

The Pollution Prevention Implementation Plan for Metal Manufacturers was prepared as part of the Iowa Pollution Prevention Initiative (IPPI) pilot project. IPPI demonstrated the team approach to small business pollution prevention technical assistance through integration of existing Iowa Small Business Development Center and Iowa Waste Reduction Center services. This cooperative effort was designed to help small businesses learn about and implement pollution prevention through recognition of pollution prevention options, comparison of costs and benefits, and evaluation of financing options. The Pollution Prevention Implementation Plan (PPIP) for Metal Manufacturers provides: • An overview of pollution prevention options, • A review of …

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Optimizing Object Invocation Using Optimistic Incremental Specialization, Jon Inouye, Andrew P. Black, Charles Consel, Calton Pu, Jonathan Walpole Jan 1995

Optimizing Object Invocation Using Optimistic Incremental Specialization, Jon Inouye, Andrew P. Black, Charles Consel, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

To make object invocation efficient, it is important to minimize overhead. In general, overhead is incurred in order to maintain transparency; with the advent of mobile computer systems, persistence, increasing security and privacy concerns, transparency becomes more expensive and overhead is increasing. Invocation mechanisms maintain transparency by finding objects, choosing communication media, performing data translation into common formats (e.g., XDR), marshalling arguments, encrypting confidential data, etc. Performing all of these operations on every invocation would lead to unacceptable performance, so designers often avoid operations by specializing object invocation for more restricted environments. For example, the Emerald compiler performs several optimizations …

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Dissociation Quotients Of Succinic Acid In Aqueous Sodium Chloride Media To 225°C, Richard Kettler, Donald A. Palmer, David J. Wesolowski Jan 1995

Dissociation Quotients Of Succinic Acid In Aqueous Sodium Chloride Media To 225°C, Richard Kettler, Donald A. Palmer, David J. Wesolowski

Department of Earth and Atmospheric Sciences: Faculty Publications

The first and second molal dissociation quotients of succinic acid were measured potentiometrically with a hydrogen-electrode, concentration cell. These measurements were carried out from 0 to 225"C over 25 ° intervals at five ionic strengths ranging from 0.1 to 5.0 molal (NaCl). The dissociation quotients from this and two other studies were combined and treated with empirical equations to yield the following thermodynamic quantities for the first acid dissociation equilibrium at 25°C: logK1a = -4.210±0.003; Δ H1̊a = 2.9±0.2 kJ-mol - 1 ; ΔS1̊a = -71±1 J-mol - 1 -K -1; and ΔCp̊,1a = -98±3 …

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Karst In Siliceous Rocks - Karst Landforms And Caves In The Auyàn-Tepui Massif (Est. Bolivar, Venezuela), Leonardo Piccini Jan 1995

Karst In Siliceous Rocks - Karst Landforms And Caves In The Auyàn-Tepui Massif (Est. Bolivar, Venezuela), Leonardo Piccini

International Journal of Speleology

During the expedition "Tepuy 93", six caves were explored in the precambrian quartzites of Roraima Group, in the Auyan-tepui massif. One of this caves reaches the depth of 370 m and a development of almost 3 km; its name is “Sima Auyan-tepui Noroeste” and it is currently the deepest cave in the world discovered in siliceous rocks The geological and morphological study of this cave has underlined again the importance of deep solutional weathering, along the network of fractures for the formation of caves in siliceous rocks. The different formation stages of the big superficial shafts, called “simas” were observed …

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Formation Of Shape-Preserving Pulses In A Nonlinear Adiabatically Integrable System, R. Grobe, Foek T. Hioe, J. H. Eberly Dec 1994

Formation Of Shape-Preserving Pulses In A Nonlinear Adiabatically Integrable System, R. Grobe, Foek T. Hioe, J. H. Eberly

Physics Faculty/Staff Publications

No abstract provided.

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Portable, High-Bandwidth Frequency-Domain Photon Migration Instrument For Tissue Spectroscopy, Steen J. Madsen, Eric R. Anderson, Richard C. Haskell, Bruce J. Tromberg Dec 1994

Portable, High-Bandwidth Frequency-Domain Photon Migration Instrument For Tissue Spectroscopy, Steen J. Madsen, Eric R. Anderson, Richard C. Haskell, Bruce J. Tromberg

All HMC Faculty Publications and Research

We describe a novel frequency-domain photon migration instrument employing direct diode laser modulation and avalanche photodiode detection, which is capable of noninvasively determinating the optical properties of biological tissues in near real time. An infinite medium diffusion model was used to extract absorption and transport scattering coefficients from 300-kHz to 800-MHz photon-density wave phase data. Optical properties measured in tissue-simulating solutions at 670 nm agreed to within 10% of those expected.

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