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1997

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Full-Text Articles in Physical Sciences and Mathematics

Changes In Channel Morphology And Flood-Plain Ecosystems Of The Green River Between The Flaming Gorge Dam, Utah And The Gates Of Lodore, Colorado, Gloria Christine Celeste Britton Jun 1997

Changes In Channel Morphology And Flood-Plain Ecosystems Of The Green River Between The Flaming Gorge Dam, Utah And The Gates Of Lodore, Colorado, Gloria Christine Celeste Britton

Masters Theses

Closure of Flaming Gorge Dam in 1962 reduced the flow rate and variability of discharge on the Green River below this dam. These changes, coupled with the decreased sediment load due to stilling and sporadic peaking in response to demand for hydroelectric power and controlled releases of up to 4500 cfs to cope with snowmelt have impacted the channel morphology and ecosystems of the main stem Green River between the Dam and the Gates of Lodore. Detailed comparative analysis of channel shape and riparian ecosystems or pre-dam and post-dam aerial photographs revealed that significant changes occurred after closure. Channel width …


Concentrations And Isotope Ratios Of Dissolved Inorganic Carbon In Denitrifying Environments, C. Nascimento, Eliot A. Atekwana, R. V. Krishnamurthy Jun 1997

Concentrations And Isotope Ratios Of Dissolved Inorganic Carbon In Denitrifying Environments, C. Nascimento, Eliot A. Atekwana, R. V. Krishnamurthy

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We measured the concentration and isotope ratio of dissolved inorganic carbon (DIC) in groundwater associated with denitrification (Corg + NO3- = CO2 + N2) in an agriculturally impacted site in southwestern Michigan. Samples with the lowest nitrate levels also had low dissolved oxygen content and were more depleted in δ13C than background groundwater. All the samples had DIC concentrations in excess of titratable alkalinity. The magnitude of this DIC in excess of alkalinity correlated with a decreasing δ13C attesting to the presence of CO2 derived from organic carbon. Carbon …


Bandwidth, Edgesum And Profile Of Graphs, Yung-Ling Lai Jun 1997

Bandwidth, Edgesum And Profile Of Graphs, Yung-Ling Lai

Dissertations

No abstract provided.


Continuous Monitoring Of Surface Deformation At Long Valley Caldera, California, With Gps, Timothy H. Dixon, Ailin Mao, Marcus Bursik, Michael Heflin, John Langbein, Ross Stein, Frank Webb Jun 1997

Continuous Monitoring Of Surface Deformation At Long Valley Caldera, California, With Gps, Timothy H. Dixon, Ailin Mao, Marcus Bursik, Michael Heflin, John Langbein, Ross Stein, Frank Webb

School of Geosciences Faculty and Staff Publications

Continuous Global Positioning System (GPS) measurements at Long Valley Caldera, an active volcanic region in east central California, have been made on the south side of the resurgent dome since early 1993. A site on the north side of the dome was added in late 1994. Special adaptations for autonomous operation in remote regions and enhanced vertical precision were made. The data record ongoing volcanic deformation consistent with uplift and expansion of the surface above a shallow magma chamber. Measurement precisions (1 standard error) for “absolute” position coordinates, i.e., relative to a global reference frame, are 3–4 mm (north), 5–6 …


The Prairie Naturalist Volume 29, No.2. June 1997 Jun 1997

The Prairie Naturalist Volume 29, No.2. June 1997

The Prairie Naturalist

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA - 1996 ▪ . R. N. Randall

BREEDING BIRD RICHNESS IN THE PRAIRIE POTHOLE REGION OF MINNESOTA ▪ . S. L. Niesar and D. E. Hubbard

UNUSUAL MIGRATION BY A WHITE-TAILED DEER FAWN IN SOUTH DAKOTA ▪ C. S. DePerno, S. L. Griffin, J. A. Jenks, and L. A. Rice

COYOTE FOOD HABITS AT DESOTO NATIONAL WILDLIFE REFUGE, NEBRASKA ▪ J. J. Huebschman, S. E. Hygnstrom, and J. A. Gubanyi

WHITE BASS GROWTH IN SOUTH DAKOTA WATERS ▪ D. W. Willis, H. D. Beck, C. A. Soupir, B. A. Johnson, G. D. Simpson, and …


Technologies For Ubiquitous Supercomputing: A Java Interface To The Nexus Communication System, Ian Foster, George K. Thiruvathukal, Steven Tuecke Jun 1997

Technologies For Ubiquitous Supercomputing: A Java Interface To The Nexus Communication System, Ian Foster, George K. Thiruvathukal, Steven Tuecke

Computer Science: Faculty Publications and Other Works

We use the term ubiquitous supercomputing to refer to systems that integrate low- and mid-range computing systems, advanced networks and remote high-end computers with the goal of enhancing the computational power accessible from local environments. Such systems promise to enable new applications in areas as diverse as smart instruments and collaborative environments. However, they also demand tools for transporting code between computers and for establishing flexible, dynamic communication structures. In this article, we propose that these requirements be satisfied by introducing Java classes that implement the global pointer and remote service request mechanisms defined by a communication library called Nexus. …


The Electrochemical Oxidation Of Organic Selenides And Selenoxides, Michael D. Ryan, Jiyi Yau, Michael Hack Jun 1997

The Electrochemical Oxidation Of Organic Selenides And Selenoxides, Michael D. Ryan, Jiyi Yau, Michael Hack

Chemistry Faculty Research and Publications

The electrochemical oxidation of alkyl and aryl selenides was investigated in acetonitrile. The oxidation of diphenyl selenide and di(4‐methylphenyl) selenide led primarily to the formation of their respective selenoxides, which were identified by exhaustive coulometric oxidation and and analysis of the products. The selenoxide itself was not observed in the cyclic voltammetry of the selenide for two reasons: first, the protonation of the selenoxide by the acid formed from the reaction of water with the cation radical and second, the formation of a selenoxide hydrate. The formation of the hydrate with diphenyl selenoxide was verified by isolation of the dimethoxy …


Numerical Simulations Of Gravity Waves Imaged Over Arecibo During The 10-Day January 1993 Campaign, Michael P. Hickey Ph.D., R. L. Walterscheid, Michael J. Taylor, William Ward, G. Schubert, Qihou Zhou, Francisco Garcia, Michael C. Kelly, G. G. Shepherd Jun 1997

Numerical Simulations Of Gravity Waves Imaged Over Arecibo During The 10-Day January 1993 Campaign, Michael P. Hickey Ph.D., R. L. Walterscheid, Michael J. Taylor, William Ward, G. Schubert, Qihou Zhou, Francisco Garcia, Michael C. Kelly, G. G. Shepherd

Publications

Recently, measurements were made of mesospheric gravity waves in the OI (5577 Å) nightglow observed from Arecibo, Puerto Rico, during January 1993 as part of a special 10-day campaign. Clear, monochromatic gravity waves were observed on several nights. By using a full-wave model that realistically includes the major physical processes in this region, we have simulated the propagation of two waves through the mesopause region and calculated the O(¹S) nightglow response to the waves. Mean winds derived from both UARS wind imaging interferometer (WINDII) and Arecibo incoherent scatter radar observations were employed in the computations as were the …


Assessment Of The Environmental Impact Of Re-Injecting Oil-Field Water Into The Miocene Clastic Sediments On The Shallow Aquifer In The Bu Hasa Oil Field, United Arab Emirates, Khalid Ali Al Amari Jun 1997

Assessment Of The Environmental Impact Of Re-Injecting Oil-Field Water Into The Miocene Clastic Sediments On The Shallow Aquifer In The Bu Hasa Oil Field, United Arab Emirates, Khalid Ali Al Amari

Theses

The Bu Hasa oil field is located about 200 km southwest of Abu Dhabi City in the U.A.E. Oil production from the field started in 1965 and a water injection program was initiated in 1970. This research is focused on the assessment of the environmental hazards to the Quaternary Liwa aquifer from either the re-injection of oil-field water into the Miocene Clastic aquifer or surface dumping into unlined pits.

Well logs, core samples, structure and isopach contour maps, stratigraphic cross sections, and water chemistry analyses were utilized in this study. Moreover, a detailed hydrogeological aquifer assessment was conducted and a …


An Improved Multi-Layer Fabrication Process For Yba2Cu3O7-X-Based Circuits, H.Q. Li, R.H. Ono, L.R. Vale, D.A. Rudman, Sy_Hwang Liou, W.H. Mallison Jun 1997

An Improved Multi-Layer Fabrication Process For Yba2Cu3O7-X-Based Circuits, H.Q. Li, R.H. Ono, L.R. Vale, D.A. Rudman, Sy_Hwang Liou, W.H. Mallison

Sy-Hwang Liou Publications

Improved via connections in structures of YBa2Cu3O7-x/SrTiO3/ YBa2Cu3O7-x (YBCO/STO/YBCO) multilayers have been made using a combined HF wet-etching and ion-milling process. The critical current density Jc of the via is as high as 2×106 A/cm2 at 76 K, and is dominated by edge contacts in the ab-plane, YBCO and Sr2AlNbO6 (SAN) multilayer test circuits were also made with this process. The 4° crossovers in a SAN test chip had a critical temperature Tc of 88 K and Jc …


Calibration Methodology And Multiple Tip Structure By Scanning Tunneling Microscopy., Michael Stephen Gossman Jun 1997

Calibration Methodology And Multiple Tip Structure By Scanning Tunneling Microscopy., Michael Stephen Gossman

Electronic Theses and Dissertations

The scanning tunneling microscope has been in commercial use just over a decade. Due to its Quantum Mechanical nature, experiments in this area have been widely publicized to the scientific community. The apparatus is steadily growing easier to use, though fundamental problems are still present. In the first chapter, an address is given on the modem theory of tunneling to rationalize the conclusions Physicists made long ago about this phenomenon. The expanded theory generalizes the mathematical motivation for attempting such unique experiments and serves as a lead-in for the major components of the apparatus. Many texts do not quantize what …


A Toolkit For Specializing Production Operating System Code, Crispin Cowan, Dylan Mcnamee, Andrew P. Black, Calton Pu, Jonathan Walpole, Charles Krasic, Perry Wagle, Qian Zhang Jun 1997

A Toolkit For Specializing Production Operating System Code, Crispin Cowan, Dylan Mcnamee, Andrew P. Black, Calton Pu, Jonathan Walpole, Charles Krasic, Perry Wagle, Qian Zhang

Computer Science Faculty Publications and Presentations

Specialization has been recognized as a powerful technique for optimizing operating systems. However, specialization has not been broadly applied beyond the research community because the current techniques, based on manual specialization, are time-consuming and error-prone. This paper describes a specialization toolkit that should help broaden the applicability of specializing operating systems by assisting in the automatic generation of specialized code, and {\em guarding} the specialized code to ensure the specialized system continues to be correct. We demonstrate the effectiveness of the toolkit by describing experiences we have had applying it in real, production environments. We report on our experiences with …


Geophysical Investigation Of Anomalous Conductivity Associated With A Hydrocarbon Contamination Site, Mike S. Nash Jun 1997

Geophysical Investigation Of Anomalous Conductivity Associated With A Hydrocarbon Contamination Site, Mike S. Nash

Masters Theses

The high electrical conductivity measured from chemical analyses from ground water below a hydrocarbon contaminated site was the focus of this study. Most theoretical studies have indicated that the electrical conductivity of hydrocarbon contamination is lower than that of the surrounding medium. Geochemical studies at other sites have shown that areas of dissolved fuel oil plume have a higher electrical conductivity. Six methods: Self Potential, Mise-a-la-Masse, Vertical Electrical Sounding, Dipole-Dipole Resistivity Profiling, Electromagnetic Induction, and Ground Penetrating Radar were all used in an attempt to see which method( s) could identify regions of high conductivity.

The findings of this study …


Search For The Bc Meson In Hadronic Z Decays, R. Barate, Manoj Thulasidas Jun 1997

Search For The Bc Meson In Hadronic Z Decays, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

A search for the Bc meson decaying into the channels Jψπ+ and Jψℓ+νℓ (ℓ = e or μ) is performed in a sample of 3.9 million hadronic Z decays collected by the ALEPH detector. This search results in the observation of 0 and 2 candidates in each of these channels, respectively, while 0.44 and 0.81 background events are expected. The following 90% confidence level upper limits are derived:Br(Z→BcXBr(Z→qq̄Br(Bc+→Jψπ+)


Measurement Of The Branching Fraction For D0 → K-Π+, R. Barate, M. Thulasidas Jun 1997

Measurement Of The Branching Fraction For D0 → K-Π+, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The branching fraction for D0 → K−π+ is measured with the statistics collected by ALEPH from 1991 to 1994. The method is based on the comparison between the rate for the reconstructed D∗+→ D0π+, D0 → K−π+ decay chain and the rate for inclusive soft pion production at low transverse momentum with respect to the nearest jet. The result is B(D0 → K−π+0 = (3.90 ± 0.09 ± 0.12)%


Efficient Parallel Processing With Optical Interconnections, Lili Hai May 1997

Efficient Parallel Processing With Optical Interconnections, Lili Hai

Dissertations

With the advances in VLSI technology, it is now possible to build chips which can each contain thousands of processors. The efficiency of such chips in executing parallel algorithms heavily depends on the interconnection topology of the processors. It is not possible to build a fully interconnected network of processors with constant fan-in/fan-out using electrical interconnections. Free space optics is a remedy to this limitation. Qualities exclusive to the optical medium are its ability to be directed for propagation in free space and the property that optical channels can cross in space without any interference. In this thesis, we present …


An Investigation Of The Oxygraphic Response Of Stressed Bovine Blood, Cristin Mckenna May 1997

An Investigation Of The Oxygraphic Response Of Stressed Bovine Blood, Cristin Mckenna

Dissertations

Oxygraphic profiles of stressed bovine blood in a temperature controlled 2 ml reactor vessel provide the basis for an investigation of blood's response to various conditions. This response is broken down into an initial response (within 3 seconds), the response over 1 hour and the response over 24 hours. Fast-assay runs which investigate the initial response display a dose-response relationship when chemically stressed by phenol. Phenol concentrations in the 1,000 ppm range indicate a decrease in dissolved oxygen (DO) and higher phenol concentrations of over 20,000 an increase in DO. In addition to phenol concentration, other factors investigated with respect …


Multi-Wavelength Infrared Imaging Computer Systems And Applications, Jun Li May 1997

Multi-Wavelength Infrared Imaging Computer Systems And Applications, Jun Li

Dissertations

This dissertation presents the development of three computer systems for multi-wavelength thermal imaging.

Two computer systems were developed for the multi-wavelength imaging pyrometers (M-WIPs) that yield non-contact temperature measurements by remotely sensing the surface of objects with unknown wavelength-dependent emissivity. These M-WIP computer systems represent the state-of-art development in remote temperature measurement system based on the multi-wavelength approach. The dissertation research includes M-WIP computer system integration, software development, performance evaluation, and also applications in monitoring and control of temperature distribution of silicon wafers in a rapid thermal process system.

The two M-WIPs are capable of data acquisition, signal processing, system …


High Speed Protocols For Dual Bus And Dual Ring Network Architectures, Yaling Zhou May 1997

High Speed Protocols For Dual Bus And Dual Ring Network Architectures, Yaling Zhou

Dissertations

In this dissertation, two channel access mechanisms providing fair and bandwidth efficient transmission on dual bus and dual ring networks with high bandwidth-latency product are proposed. In addition, two effective priority mechanisms are introduced to meet the throughput and delay requirements of the diverse arrays of applications that future high speed networks must support.

For dual bus architectures, the Buffer Insertion Bandwidth Balancing (BI_BWB) mechanism and the Preemptive priority Bandwidth Balancing (P_BI_BWB) mechanism are proposed. BI_BWB can significantly improve the delay performance of remote stations. It achieves that by providing each station with a shift register into which the station …


Sampling And Analysis Of Trace Level Volatile Organic Compounds From Air Via Membrane Permeation, Naihong Zhu May 1997

Sampling And Analysis Of Trace Level Volatile Organic Compounds From Air Via Membrane Permeation, Naihong Zhu

Dissertations

The objective of this study is to develop air sampling techniques using membrane permeation. Two novel techniques for sampling and analysis of trace level VOCs from air via membrane permeation are presented:

  1. selective concentration of VOCs into a canister using a membrane permeator;
  2. on-line membrane extraction for direct introduction of VOCs from air emissions into a gas chromatograph.

In the membrane permeator-canister sampling system (MPCS), the air sample containing trace level VOCs as well as some interferences such as moisture are passed through the membrane module. Polydimethyl siloxane membrane used in this research is highly permeable to organic compounds, but …


On Document Filing Based Upon Predicates, Zhijian Zhu May 1997

On Document Filing Based Upon Predicates, Zhijian Zhu

Dissertations

This dissertation presents a formal approach to modeling documents in a personal office environment, proposes a heterogeneous algebraic query language to manipulating objects (folders) in the document model, and investigates a predicate-driven document filing system for automatically filing documents.

The document model was initially proposed in [38] which adopts a very natural view for describing the office documents using the relational and object-oriented paradigms. The model employs a dual approach to classifying and categorizing office documents by defining both a document type hierarchy and a folder organization. This dissertation extends and specifies formally the document model. Documents are partitioned into …


Assessment Of Potential Operating Benefits Incurred By Implementing Iso 14001 : Five Case Studies From The New Jersey Chemical Industry, Stefanie Gitter May 1997

Assessment Of Potential Operating Benefits Incurred By Implementing Iso 14001 : Five Case Studies From The New Jersey Chemical Industry, Stefanie Gitter

Theses

Environmental management is an important aspect of strategic planning and competitiveness for many businesses. Environmental management systems (EMS) are operating policies that are established to help a company measure progress towards goals set forth in a strategic environmental plan. A growing number of EMS models are being used by countries and industry groups, so the International Standards Organization (ISO) developed one model to prevent duplicate efforts which can result when companies try to meet the import requirements of different countries.

The ISO-EMS model is a series of standards, and ISO 14001 is the first to be published. Companies will be …


A Graphical Environment For Change Detection In Structured Documents, Girish A. Patel May 1997

A Graphical Environment For Change Detection In Structured Documents, Girish A. Patel

Theses

Change detection in structured documents (e.g. SGML is important in data warehousing, digital libraries and Internet databases. This thesis presents a graphical environment for detecting changes in the structured documents. We represent. each document by alp ordered labeled tree based on the underlying markup language. We then compare two documents by invoking previously developed algorithms for approximate pattern matching and pattern discovery in trees. Several operators are developed to support. the comparison of the documents; graphical devices are provided to facilitate the use of the operators. We believe the proposed tool is useful for not only document management, but also …


Object Oriented Partitioning For A Medical Vocabulary Based On Semantic Network, Mansnimar Singh May 1997

Object Oriented Partitioning For A Medical Vocabulary Based On Semantic Network, Mansnimar Singh

Theses

Computers have become ubiquitous and indispensable part of everyday life both for personal use and in the workplace. Medicine is one of the few domains that has not fully adopted computerization. One impediment to this emanates from a communication gap between the computer science professional and the medical professional. Besides, medical terminology is full of synonyms and medical professionals use them according to their personal preferences. This lack of common terminology has prevented sharing of knowledge and automating data processing, resulting in the healthcare information explosion.

Semantic network models have been developed to represent medical concepts and to provide a …


Design And Implementation Of On-Line Metrics, Ashok Vantipalli May 1997

Design And Implementation Of On-Line Metrics, Ashok Vantipalli

Theses

The performance of a software product plays an important role in the software industry to survive the tough competition given by the other software vendors. The real test for a software product starts after its release when it is extensively used by the end users and in different environments. And the software goes through a number of tests by the end users which can be very different and insufficient from the regression tests the software vendor performed on it. This critical issue; requires each vendor to have a department mainly dealing with the testing and analysing the performance of a …


Development Of Methods For Field Determination Of Chromium (Vi) In Water And Groundwater, David John Chesbro May 1997

Development Of Methods For Field Determination Of Chromium (Vi) In Water And Groundwater, David John Chesbro

Theses

In this study, methods for the determination of chromium (VI) in fresh water at low ppb levels for the use under field conditions were developed. The plan was to devise a simple and inexpensive on-site field method which would be useable by people who are not professional chemists. An investigation was carried out to develop a preconcentration and determination procedure for the analysis of chromium (VI) using anion-exchange membranes and/or resins. The chromium (VI) would be sorbed to the solid support and then treated with 1 ,5-diphenylcarabzide, a specific colorimetric reagent for chromium (VI), which forms a red complex upon …


Admission Control Policies For Internet File Transfer Protocols, Simon Holmes A Court May 1997

Admission Control Policies For Internet File Transfer Protocols, Simon Holmes A Court

Dartmouth College Undergraduate Theses

Server congestion is a major cause of frustration with the Internet. It is not uncommon for a server with a new release of popular software to be swamped by many times more clients than it can possibly handle. Current Internet file transfer protocols, namely FTP and HTTP, do not have any policy to regulate client admission. In this thesis we are concerned with server admission policies that will improve clients' experience with servers under heavy load. Using a purpose-built network simulator, we compare the prevalent protocols with two new protocols that include policies taken from processor scheduling. By applying more …


An Information Retrieval System For Performing Hierarchical Document Clustering, Eric Hagen May 1997

An Information Retrieval System For Performing Hierarchical Document Clustering, Eric Hagen

Dartmouth College Undergraduate Theses

This thesis presents a system for web-based information retrieval that supports precise and informative post-query organization (automated document clustering by topic) to decrease real search time on the part of the user. Most existing Information Retrieval systems depend on the user to perform intelligent, specific queries with Boolean operators in order to minimize the set of returned documents. The user essentially must guess the appropriate keywords before performing the query. Other systems use a vector space model which is more suitable to performing the document similarity operations which permit hierarchical clustering of returned documents by topic. This allows "post query" …


Solomon's Sea And The Biblical Π, Andrew Simoson May 1997

Solomon's Sea And The Biblical Π, Andrew Simoson

ACMS Conference Proceedings 1997

From I Kings 7:23, the apparent diameter and circumference of a circular ring are given as 10 and 30 cubits which suggests that the Biblical value of π is 3 rather a number closer to π. However we recount seven different somewhat whimsical explanations as to why this conclusion is overly-hasty.


Mathematics And Values: Can Philosophy Guide Projects?, Michael H. Veatch May 1997

Mathematics And Values: Can Philosophy Guide Projects?, Michael H. Veatch

ACMS Conference Proceedings 1997

The philosophy of mathematics has provided insight on questions of foundations and mathematical truth; however, it has not been very fruitful in guiding the practice of mathematics. This paper attempts to find points of contact between a Christian worldview and the choice of mathematical projects and methods. Three areas are considered: (i) dubitability in current research, (ii) the intrinsic value of contemporary mathematics to contemporary society, and (iii) the affirmation of human value in the use of mathematics. Finally, a framework for valuing mathematics is proposed as an encouragement to think more deeply about how a Christian might choose a …