6,752 research outputs found
Paper Session I-B - Laser Communications Utilizing Molniya Satellite
The telecommunications evolution has advanced to level where bandwidth is now a limiting factor for data transmission. The use of laser communications with satellites is not a new idea and has been proven ,Ref [3], in certain configurations using geostationary orbits. The purpose of this thesis is to explore the use of laser technology for land based terminals above the 80-degree latitude. After establishing an understanding of the nature of the mathematical model for the turbulent effects on laser beams, the investigation will utilize the Molniya satellite orbit characteristics with the goal of eliminating or reducing the tracking complexity
Shelley Lynn Phillips in a Mezzo-Soprano Senior Voice Recital
This is the program for the senior mezzo-soprano recital of Shelley Lynn Phillips, accompanied by pianist, Terri Lucas, and organist, Dr. Russell Hodges. The recital was held on February 5, 1991, in the Mabee Fine Arts Center Recital Hall
Response of glacier flow and structure to proglacial lake development and climate at Fjallsjökull, south-east Iceland
ABSTRACTOver recent decades, the number of outlet glaciers terminating in lakes in Iceland has increased in line with climate warming. The mass-balance changes of these lake-terminating outlet glaciers are sensitive to rising air temperatures, due to altered glacier dynamics and increased surface melt. This study aims to better understand the relationship between proglacial lake development, climate, glacier dynamics and glacier structure at Fjallsjökull, a large, lake-terminating outlet glacier in south-east Iceland. We used satellite imagery to map glacier terminus position and lake extent between 1973 and 2016, and a combination of aerial and satellite imagery to map the structural architecture of the glacier's terminus in 1982, 1994 and 2011. The temporal evolution of ice surface velocities between 1990 and 2018 was calculated using feature tracking. Statistically significant increases in the rate of terminus retreat and lake expansion were identified in 2001, 2009 and 2011. Our surface velocity and structural datasets revealed the development of localised flow ‘corridors’ over time, which conveyed relatively faster flow towards the glacier's terminus. We attribute the overall changes in dynamics and structural architecture at Fjallsjökull to rising air temperatures, but argue that the spatial complexities are driven by glacier specific factors, such as basal topography.</jats:p
Managing Bison to Restore Biodiversity
Prior to their demise in the late 1800s, bison coexisted with and helped sustain a diverse and spectacular assemblage of animals and plant communities on the Great Plains. Bison, in concert with fire, exerted strong control on the structure of the vegetation by grazing, trampling, and wallowing. The changes in the vegetation induced changes in many animal populations. These impacts, coupled with the bison\u27s role as the major converter of grass to meat, so greatly affected other species that some have called bison a keystone species in the Great Plains ecosystem. The black-tailed prairie dog, dependent on bison grazing over a large part of the Great Plains, amplified the keystone influence of bison by its own grazing and burrowing activities and its utility as prey. Although modern bison-growing practices usually will preclude restoration of the large predators and scavengers that once were a part of the great faunal spectacle, other species can return, often even on small acreages. Maintenance of a habitat mosaic is the key to restoring some of the original biodiversity lost to the historic pursuit of single species pastoralism
Raising Cash Under Duress And The Role Of Cash Value Life Insurance: An Educational Example
Consumers face hard choices when they need cash quickly. Hard choices can lead to emotional or economically unsound decisions. Traditional classroom discussions of raising funds to pay for expenses usually focus on generating income, borrowing, or the sale of real and financial assets, if hardship is discussed at all. However, many families have additional “non-traditional” sources of cash. This article examines the use of life insurance surrenders and policy loans as a source of funds for both routine funding needs as well as a source of emergency financing. The article concludes with a review of the economic considerations of life insurance for Insurance and Financial Planning educators and students
Fish Assemblages and Benthic Biota Associated with Natural Hard-Bottom Areas in the Northwestern Gulf of Mexico
We report new observations of fish and benthic invertebrate assemblages at shallow-water (\u3c35 m depth), hard-bottom sites in the northwestern Gulf of Mexico. The biota of these previously unstudied areas and of three high-relief features in deeper water was observed during May 1980 using a combination of diver reconnaissance, videotape surveys, still-camera photography, and collection of invertebrates for identification. The six hard-bottom sites in shallow water typically comprised, small, often patchy, rock outcrops, and the associated sessile invertebrates included hydroids, bryozoans, sponges, octocorals, and ahermatypic stony corals. Sea urchins and arrow crabs were the most common motile epifauna. Fish assemblages were typified by red snapper, Atlantic spadefish, blue runner gray triggerfish, sheepshead, and tomtate. Three deeper stations had many of the same fish and invertebrate species, but also possessed a more tropical assemblage including fire corals, antipatharians, spiny lobsters, and a variety of tropical fish species. Hermatypic corals characteristic of some large, offshore banks were not abundant at any of the sites.
Differences in the composition of fish assemblages between nearshore and deeper stations parallel those previously observed at petroleum platforms in the area. Shallow-water stations presumably experience a greater seasonal temperature range and lower absolute temperatures in winter and may be exposed to stresses such a lowered salinity and depleted oxygen levels due to their relative proximity to Mississippi River discharge. The fauna of these shallow hard-bottom sites has predominantly warm-temperate rather than tropical affinities
Partial-Transfer Absorption Imaging: A versatile technique for optimal imaging of ultracold gases
Partial-transfer absorption imaging is a tool that enables optimal imaging of
atomic clouds for a wide range of optical depths. In contrast to standard
absorption imaging, the technique can be minimally-destructive and can be used
to obtain multiple successive images of the same sample. The technique involves
transferring a small fraction of the sample from an initial internal atomic
state to an auxiliary state and subsequently imaging that fraction absorptively
on a cycling transition. The atoms remaining in the initial state are
essentially unaffected. We demonstrate the technique, discuss its
applicability, and compare its performance as a minimally-destructive technique
to that of phase-contrast imaging.Comment: 10 pages, 5 figures, submitted to Review of Scientific Instrument
The exception or the rule? Historical survey and analytical breakdown of Constantinople’s missionary work 398-1453
No abstract available
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