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Manufacturing flexible light-emitting polymer displays with conductive lithographic film technology
We report on a new low-cost manufacturing process for flexible displays that has the potential to rapidly expand the market into areas that have traditionally been outside the scope of such technology. In this paper we consider the feasibility of using offset-lithography to deposit contacts for polymer light-emitting displays. We compare and contrast manufacturing criteria and present a case study detailing our initial results. It is expected that these developments will stimulate further progress in multilayer device
fabrication.
Cheap, flexible conductive interconnects have the potential to find applications in a wide variety of device structures. For the more challenging exploitation areas in multilayer devices, such as displays, it was found that the properties of conductive lithographic films were not optimal in their current form. Three parameters (conductivity, surface roughness and surface work function) were identified as critical to device fabrication. Calendering and electroless plating were investigated as methods to improve these properties. Both methods aimed to modify the surface roughness and conductivity, with the plating study also modifying the work function
Genetic Analysis of the Southern Yellow Bat (Dasypterus ega)
For this research project I examined the genetic variation of the Southern yellow bat, Dasypterus ega. No previous genetic work has been done on this species of conservation concern even though genetic diversity is an important aspect of species conservation. I used a microsatellite analysis to examine the level of genetic variation of D. ega in southern Texas. I analyzed 75 bats from 15 counties using six loci that were used in a close relative, the Eastern red bat (Lasiurus borealis). There were 3-18 alleles at each locus and the level of heterozygosity was low (0.385). This value was lower than endangered species Corynorhinus townsendii ingens and much lower than that reported for a common, widespread species of bat, L. borealis. This indicates that D. ega, recognized as a âthreatenedâ species in Texas, might have experienced a loss of genetic diversity due to being a leading-edge population, genetic drift, or a genetic bottleneck
The effects of groundwater seepage on stream regimen : a laboratory study
The effects of\u27 groundwater seepage on the competence, bed rough ness, and water surface slope of small streams were studied in two laboratory fumes. The larger fume is 20 feet long, 3t feet wide, and 18 inches deep; the smaller flume is 12 feet long, 6 inches wide, and 10 inches deep. Both flumes are equipped so that groundwater seepage through the stream bed can be controlled and monitored.
In the absence of bedforms, upward (positive) seepage has little effect on stream competence or transport rate, even when quicksand conditions are reached. The decrease in effective grain density brought about by uptward seepage might possibly be compensated entirely or in part by a decrease in surface drag and an increase in form drag on individual grains on the stream bed.
In the presence of bedforms such as ripples or dunes, however, seepage appears to have an inverse relationship to steepness of bedform faces (angle of repose), bottom roughness and turbulence, and transport rate. The inverse relationship of seepage to transport rate under these conditions is caused by steepening of bedform faces under conditions of downward seepage which results in greater bottom roughness and turbulence than in runs without seepage. Conversely, upward seepage tends to decrease the steepness of the bedforms, thereby decreasing bottom roughness, turbulence, and transport rate. The angle of repose on bedforms was increased to an average of about 43 degrees under conditions of downward seepage in much a hydraulic seepage gradient of -1.4 was present, as compared to an average angle of repose of about 33 degrees without seepage. A hydraulic seepage gradient of about +0.8 decreased the average angle of repose to about 27 degrees.
With no seepage and with upward seepage, relative roughness of the stream bed in the 13.rger flume ranged from 0.56 to 0.83 (average value of 0.62) whereas with downward seepage it increased to 1.05. This increase in bed roughness, however, did not increase flow resistance sufficiently to cause an increase in the slope of the water surface (measured to within 0.005 ft/ft).
When bedforms are absent, downward {negative) seepage appears to have little effect on competence or transport rate if clear water is present in the channel. If the water is sufficiently turbid, however, the surface o:t the stream bed becomes clogged by the infiltration of the turbid water. This clogging, or mid-seal effect, decreases the permeability of the stream bed until the sediment underlying the uppermost layer of the bed becomes unsaturated. When this occurs, the weight of the water in the channel must be supported. by the grains lying within the mid-seal layer. The affective density of the grains may be increased several hundred times, resulting in a cessation of bedload transport and an increase in compressive strength of the stream bed. Effective grain density under conditions varies inversely with grain diameter and directly with the depth of water 1n the channel. A mud seal can develop even under conditions of high-regime flow with bedload transport occurring in the form of a moving carpet. If punctured, the seal, is self-healing, provided sufficient suspended sediment is present. It seems likely that natural mud seals may be present on the bed or many irrigation canals and ephemeral steams such as arroyos and alluvial fan streams
Relationship of the Turtle, Forest, and Park rivers to the history of glacial Lake Agassiz
The thesis here abstracted was written under the direction of Wilson M. Laird and approved by John R. Reid and Alan M. Cvancara as members of the examining committee, of which Dr. Laird was Chainnan.
During the summer of 1964 a study of the Turtle, Forest, and Park river valleys was undertaken to find evidence of former changes in river regimen. The regimen of rivers once draining into glacial Lake Agassiz was probably affected by changes in base level associated with fluctuations of that lake. The Turtle, Forest, and Park rivers, which presently flow eastward across the bed of Lake Agassiz, show little irrefutable evidence of base level fluctuations.
Numerous terrace-like surfaces are found in these valleys from the area of the beaches headward. The lowest and most prominent surface is about 8 to 12 feet above river level. Overbank deposition occurs on this surf ace during periodic floods. It is the ref ore a product of the present river regimen and is an active floodplain. Other, higher, surfaces in these valleys are, however, true terraces. Most are unpaired and none can be traced for more than one mile. None can be directly related to a particular stand of glacial Lake Agassiz.
Twenty-five feet of sandy silt exposed in a cutbank in the Park River valley suggests fluctuations in base level. Erosion of the valley may have occurred during the Lake Agassiz I-II interval, followed by aggradation as base level rose during Lake Agassiz II time. Sub sequent to drainage of the lake, the river has eroded this fill.
Seven mussel species were collected from cutbanks on the Turtle River. They represent essentially a small river or creek fauna. Three of these species do not presently inhabit the river
Stormwater Inputs in Urban Streams: Impact and Persistence of Effects on Stream Temperature
Stream temperature is an important metric for determining the health of a stream system, and derived from complex interactions between climate, weather, and local landscape characteristics. In urban areas, stream temperature is additionally influenced by impervious surfaces as well as stormwater infrastructure that translates water quickly to stream channels. Disentangling the impacts of spatial and temporal drivers of the stream temperature regime is therefore a complex task. To improve understanding of spatial and temporal variability in stream temperatures, we combined in situ stream temperature loggers with thermal infrared (TIR) imagery collected via unmanned aerial vehicles (UAV) along a 2.25 km section of creek in Syracuse, NY. TIR imagery was used document the heterogeneity of stream temperature as impacted by a natural spring and several stormwater inputs across the stream channel and down the length of a stream for three flights in May, June, and July of 2017. Thermal heterogeneities derived from stormwater culverts were observed to persist as far as 290 m downstream from their source depending on the time of year. Reach observations and weather station data were combined with TIR imagery to calibrate a deterministic stream temperature model using a modified version of HFLUX 3.0. Stream temperatures were simulated in HFLUX for a five-day period, after a two day warm up, surrounding monthly flights using different combinations of stormwater discharge and temperature. The use of two metrics derived from the TIR data, an âInitial Impactâ (on stream temperature) and âEffect Durationâ, enabled spatial model calibration alongside temporal calibration to iButton observations at the end of the reach. Discrepancies between best models fits through space and best model fits through time establish that model approaches should incorporate errors in multiple dimensions. Overall, this study demonstrates that stormwater inputs in northeastern watersheds may cool mean stream temperatures, with effects that can persist for hundreds of meters downstream. Beyond the impact of stormwater, we also show that UAV-based TIR can be particularly useful for documenting these impacts when paired with in situ sensors. Finally, we find that calibrating models in multiple dimensions can more accurately simulate spatio-temporal hydrologic processes and mixing between urban water sources and the main channel
A CONJOINT ANALYSIS OF NEW FOOD PRODUCTS PROCESSED FROM UNDERUTILIZED SMALL CRAWFISH
Attributes for two value-added seafood products derived from underutilized crawfish are analyzed using conjoint data from seafood restaurants in the southern region of the United States. Preferences for the products' form, price, and flavor attributes were tested. Statistical tests revealed that the attribute interactions were not significant, and part-worth utilities for all main effects were estimated using an additive preference model. Results indicate that the new crawfish products should be marketed as a high-quality fresh soup base or seafood stuffing, priced between 30% and 50% of the cost of fresh crawfish tail meat.Conjoint analysis, Seafood, Value added, Marketing,
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