Physical Sciences and Mathematics Commons^™

Accelerating The Simulation Of Wireless Cellular Systems, Luiz Felipe Perrone

Dissertations, Theses, and Masters Projects

The simulation of comprehensive models for cellular wireless systems poses a computational burden of great proportions. When a sub-model for transmitter power level control is included in the simulation, a continuous process in discrete-time is introduced, requiring traditional execution to advance in small, regular time-steps. to accelerate these simulations, we propose the use of interval jumping, a novel technique which allows time to progress in adaptive, irregularly-sized jumps in time. The foundations for this mechanism are laid out in the light of the simulation of a complex simulation model which includes teletraffic, radio propagation, channel allocation, transmitter power control, and …

Surface Processing By Rfi Pecvd And Rfi Psii, Lingling Wu

Dissertations, Theses, and Masters Projects

An RFI plasma enhanced chemical vapor deposition (PECVD) system and a large-scale RF plasma source immersion ion implantation (PSII) system were designed and built to study two forms of 3-D surface processing, PECVD and PSII. Using the RFI PECVD system, Ti-6Al-4V substrates were coated with diamond-like carbon films with excellent tribological and optical properties. as an innovation, variable angle spectroscopic ellipsometry (VASE) was successfully applied for non-destructive, 3-D, large-area tribological coatings quality investigation.;Based on the experience with the RFI PECVD system, a large-scale RFICP source was designed and built for the PSIL Langmuir probe and optical emission spectroscopy studies indicated …

The Use Of Long-Lived Tracer Observations To Examine Transport Characteristics In The Lower Stratosphere, Gretchen Scott Lingenfelser

Dissertations, Theses, and Masters Projects

No abstract provided.

The Dehydrochlorination Mechanism Of The Internal Allylic Chloride Structure In Poly(Vinyl Chloride), Lynda B. Payne

Dissertations, Theses, and Masters Projects

No abstract provided.

On The Sources Of Weddell Gyre Antarctic Bottom Water, Michael P. Meredith, Ricardo A. Locarnini, Kim A. Van Scoy, Andrew J. Watson, Karen J. Heywood, Brian A. King

CCPO Publications

In March-April 1995, as part of the World Ocean Circulation Experiment section A23, we completed 49 hydrographic stations across the Weddell Gyre and southern Antarctic Circumpolar Current, from the Antarctic continental shelf (72.5°S, 16.5°W) to South Georgia (55°S, 34.5°W). Chlorofiuorocarbon (CFC11, CFC-12, and CFC-113) data collected at these stations reveal that distinct sources renew the Antarctic Bottom Water (defined as waters with potential temperatures less than 0°C) of the Weddell Gyre. Weddell Sea Bottom Water (defined as waters with potential temperatures less than- 0.7°C) formed in the western Weddell Sea has CFC concentrations about 5 to 6 times higher in …

Gis Data: Piankatank River, Virginia Shoreline Management Model, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Data

The Shoreline Management Model is a GIS spatial model that determines appropriate shoreline best management practices using available spatial data and decision tree logic. Available shoreline conditions used in the model include the presence or absence of tidal marshes, beaches, and forested riparian buffers, bank vegetation cover, bank height, wave exposure (fetch), nearshore water depth, and proximity of coastal development to the shoreline. The model output for shoreline best management practices is displayed in the locality Comprehensive Map Viewer. One GIS shapefile is developed that describes two arcs or lines representing practices in the upland area and practices at the …

Managing The Acidity Of Abandoned Water Filled Coal Mining Voids In Collie (Western Australia) Using Organic Matter, Scott A. Thompson

Theses: Doctorates and Masters

The effectiveness of using organic matter additions to increase pH in abandoned water filled coal mining voids in Collie was investigated. Previous studies have demonstrated that passing acidic drainage through organic matter increased the waters pH. Laboratory trials using intact sediment cores (collected from Ewington, Collie, Western Australia) were used to assess the effects of additions of hay, manure and mulched vegetation on pH, nutrients an sulphate levels. In a series of experiments the effect of different quantities of organic material, sulphate reducing bacterial inoculations and alkalinity generation were measured. A subsequent field experiment was conducted to examine the impact …

Effects Of Polychlorinated Biphenyl Exposure On Development And Sexual Differentiation In Ranid Tadpoles, Mary J. Rybitski

Dissertations, Theses, and Masters Projects

The effects of AroclorRTM1242 exposure on developing amphibians were examined by exposing southern leopard frogs, Rana sphenocephala, to a contaminated diet throughout the larval period. Treatment groups consisted of an untreated control, a solvent control, 17beta-estradiol, and three PCB doses (10, 100, and 1000 mug/g). PCB accumulation and biotransformation were examined. Effects of PCB exposure on metamorphosis and sexual differentiation were assessed. PCB accumulation was not statistically different between the egg masses. Levels of PCBs in the tissues differed in a dose related manner. Within treatments, body weight appeared to be the major factor correlated with PCB concentration. Congener patterns …

Semantic Software Scouts For Information Retrieval, John J. Rehder

Dissertations, Theses, and Masters Projects

A new concept for information storage and retrieval is proposed that links chunks of information within and among documents based on semantic relationships and uses those connections to efficiently retrieve all the information that closely matches the user's request. The storage method is semantic hypertext, in which conventional hypertext links are enriched with semantic information that includes the strength and type of the relationship between the chunks of information being linked. A retrieval method was devised in which a set of cooperating software agents, called scouts, traverse the connections simultaneously searching for requested information. By communicating with each other and …

Studies In Hard Pion Photoproduction, Christian Jens Wahlquist

Dissertations, Theses, and Masters Projects

The production of high transverse momenta mesons via polarized photoproduction can be a means of determining the parton structure of the target. at the regions of highest transverse pion momenta, kT, it can be shown that short distance, direct, pion production dominates and is sensitive to the polarized quark distributions. as the produced pions transverse momenta decreases the importance of pions produced through fragmentation following photon-gluon fusion increases. This process give us sensitivity to the form of the polarized gluon distribution. Both processes are calculable with perturbative Quantum Chromodynamics (pQCD) due to the high kT of the pion produced. Numerical …

The Attempted Synthesis Of 4,4'-Bis(Dimethylamino)Azobenzene-3,3'-Disulfonylchloride As A Cap For Beta-Cyclodextrin, Katherine M. Ross

Dissertations, Theses, and Masters Projects

No abstract provided.

The Link Between Climate Warming And Break-Up Of Ice Shelves In The Antarctic Peninsula, Ted A. Scambos, Christina L. Hulbe, Mark A. Fahnestock, Jennifer Bohlander

Geology Faculty Publications and Presentations

A review of in situ and remote-sensing data covering the ice shelves of the Antarctic Peninsula provides a series of characteristics closely associated with rapid shelf retreat: deeply embayed ice fronts; calving of myriad small elongate bergs in punctuated events; increasing flow speed; and the presence of melt ponds on the ice-shelf surface in the vicinity of the break-ups. As climate has warmed in the Antarctic Peninsula region, melt-season duration and the extent of ponding have increased. Most break-up events have occurred during longer melt seasons, suggesting that meltwater itself, not just warming, is responsible. Regions that show melting without …

Tributaries To West Antarctic Ice Streams: Characteristics Deduced From Numerical Modelling Of Ice Flow, Christina L. Hulbe, Ian R. Joughin, David L. Morse, R. A. Bindschadler

Geology Faculty Publications and Presentations

A network of relatively fast-flowing tributaries in the catchment basins of the West Antarctic ice streams transport ice from the inland reservoir to the heads of the ice streams. Branches of the network follow valleys in basal topography, but not all valleys contain tributaries. We investigate the circumstances favoring tributary flow upstream of Ice Streams D and E, using a combination of observation and numerical modelling. No consistent pattern emerges. The transition from tributary to ice-stream flow occurs smoothly along the main tributary feeding into the onset of Ice Stream D, with ice thickness being relatively more important upstream, and …

Answering Local Wetlands Boards Needs Regarding Guidance In Investigating Wetlands Violations : Final Report To The United States Environmental Protection Agency, Wetlands Protection State Development Project Period July 1, 1998-June 30, 2000, Kirk J. Havens, Bartlett N. Theberge

Reports

No abstract provided.

The Crest, Winter 2000, Virginia Institute Of Marine Science

Reports

Table of Contents:

• VIMS Director Invited to Speak in China Finfish Aquaculture Updates
• Riparian Buffer Demonstration Sites
• Bay-Sustaining Life Bustling On The Bottom
• New Technology Boosts Billfish Survivability Research
• A Profile of the Aquaculture Molecular Genetics Laboratory: Probing the DNA of the Oyster and its Parasite Perkinsus marinus (Dermo)
• Origin of MSX in Eastern Oyster Documented by VIMS Scientists
• Guess What Really Takes A Blue Crab's Breath Away?
• Catch and Release Symposium Tackles Tough Salt Water Fishing Issues
• Teaching Marsh Update
• Oyster Reef Habitat Restoration Book now Available
• Future Alterations to the Yangzi Estuary

A Determination Of Parentage, Mating System, And Genetic Diversity In A Captive Population Of The Straw-Colored Fruit Bat (Eidolon Helvum), Jan Zinck

Dissertations and Theses

Small populations tend to lose genetic variability. The magnitude of this loss is influenced by the number of founding individuals, the genetic diversity of the founders, and the species mating system. Genetic variability is the basis of adaptive evolution, and the loss of genetic variability may have harmful effects on development, growth, and survival. Therefore, a primary management goal for small, captive populations is the retention of genetic variability. Of considerable importance to conservation biology is the determination of parentage, from which mating, genetic, and demographic information can be derived. Microsatellites provide a robust molecular evolutionary tool for the study …

The Long-Term Viability Of A Zero-Valent Iron Permeable Reactive Barrier, Stuart Cowburn

Dissertations and Theses

Zero-valent iron permeable reactive barriers (PRB's) hold significant potential as a tool for groundwater remediation. Uncertainties remain, however, as to the effective lifetime of Fe⁰ barrier technology under full-scale operational conditions. Potential limits on barrier lifetime include reductions in permeability due to clogging by precipitates and oxidation of all Fe⁰ prior to the exhaustion of the contaminant source.

A 46 m long, 0.6 m wide, and 7.3 m deep Fe⁰ PRB was installed at the US Coast Guard Support Center, Elizabeth City, NC, in June 1996. The barrier was designed to remediate groundwater principally contaminated with Cr(VI) …

Resource Notes-Academic Year 1999-2000

Conservation and Survey Division

No abstract provided.

Resource News-Spring 2000

Conservation and Survey Division

No abstract provided.

Resource News-Summer 2000

Conservation and Survey Division

No abstract provided.

Some Post-Pliocene Buried Soils Of Central United States, James Thorp, W. M. Johnson, E. C. Reed

Conservation and Survey Division

No abstract provided.

Principal Reservoirs In Nebraska, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Calamus River Valley Map, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

County Names/Numbers, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Natural Resource Districts In Nebraska, Nebraska Natural Resource Commission

Conservation and Survey Division

No abstract provided.

Deep Well Guide/Grey Files 121.1, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Nebraska Information, Number Of Topographical Maps Per County, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Nebraska Information, Oregon Trail, Station Sites, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Oregon Trail/Other Points Of Interest In Nebraska, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.

Overland Trails, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.