4,972 research outputs found
Quick Searching at the Library: A Usability Study on Combining Web Scale Discovery Tools for the Ultimate Search Interface
Research was conducted at the University of North Carolina at Chapel Hill to study the usability of two search interfaces â one tabbed interface similar to the current UNC-CH library homepage and one with a single search bar similar to Google. The UNC-CH Libraries also developed a combined search tool that pulls library resources from the Serials Solutions Summon service and from the Endeca-powered catalog. The usability test involved several tasks to determine interface preference, autosuggestâs utility, and the optimal location for the âbest betsâ recommendation box within the results. The usability testing also included having participants respond to a proposed library homepage to gather feedback for a redesign project. The resulting data showed users preferred the tabbed widget, but overall were not averse to the use of the simple widget on the proposed library homepage since the information they found most important was still available. Researchers observed the adaptability of users to search tools as long as those tools provided them with the results they needed to perform research
A Biomechanical Comparison Of Single, Double, and Triple Axels
To be competitive at the national and international levrels, figure skaters today must perform complex athletic skills such as triple axels and quadruple toe loops. While numerous skaters now attemping these jumps in competition, very few are executing them consistently, particularly at the end of their program or in combination with other jumps. In this study, a 3D kinematic analysis of five elite male skaters was undertaken to compare characteristics of single, double, and triple axels. If figure skating coaches can learn what these skaters do differently when executing a triple axel as compared to a single or double axel, perhaps they will be able to more successfully teach this difficult skill to developing skaters. In this study, three 60 Hz video cameras were focused on a "jump zone" in which skaters were instructed to take off for all jumps. Three attempts of each jump type per skater were recorded, and each skater's best jump of each type, as evaluated by two coaches, was digitized using the PEAK Performance, Inc. motion analysis system. Numerous kinematic parameters including jump height, take-off angle, take-off velocity, and rotational velocity were computed and compared for the different jump types and different skaters. Additional measurements such as jump distance, skid distance, and skid width were made from skaters' marks on the ice. The results of this study show that despite diversity in skaters' indivitual jump styles, consistent differences between single, double, and triple axels can be observed. For example, skaters increase their number of revolutions by increasing their rotational velocity, not by increasng their jump height or time in the air. The study also shows that skaters triple axels travel only 70 percent of thc distance of their single axels, an observation attributable to skaters' greater skid distance, greater take-off angle, and consequently lower horizontal velocity at take-off in their triple axels as compared to their angle or double axels. Such observations suggest that achieving a high rotational (in excess of 5 revolutions per second) by generating angular momentum at take-off and by "pulling in" tightly to minimize the moment of inertia about the spin axis is a key to consistently performing the triple axel jump
Blended Learning Environments in Higher Education: A Case Study of How Professors Make it Happen
Blended learning has become a prominent method of course content delivery in higher education. Researchers have found that motivation, communication, and course design are three factors that contribute to the overall success of blended learning courses and studentsâ satisfaction with blended learning courses. This qualitative study also found that course preparation emerged through the participant interviews as a contributing factor. What remains unclear, however, is whether faculty take these factors into consideration when preparing to teach a blended learning course and, if so, how. In this study, a collective case study of five faculty of blended learning courses was conducted to investigate how they prepared to teach a blended learning course and how they considered course preparation, course design, communication, and motivation. The findings suggest that the faculty did consider these four factors to varying degrees
Effect of grazing on ship rat density in forest fragments of lowland Waikato, New Zealand
Ship rat (Rattus rattus) density was assessed by snap-trapping during summer and autumn in eight indigenous forest fragments (mean 5 ha) in rural landscapes of Waikato, a lowland pastoral farming district of the North Island, New Zealand. Four of the eight were fenced and four grazed. In each set of four, half were connected with hedgerows, gullies or some other vegetative corridor to nearby forest and half were completely isolated. Summer rat density based on the number trapped in the first six nights was higher in fenced (mean 6.5 rats haâ1) than in grazed fragments (mean 0.5 rats haâ1; P = 0.02). Rats were eradicated (no rats caught and no rat footprints recorded for three consecutive nights) from all eight fragments in JanuaryâApril 2008, but reinvaded within a month; time to eradication averaged 47 nights in fenced and 19 nights in grazed fragments. A second six-night trapping operation in autumn, 1â3 months after eradication, found no effect of fencing (P = 0.73). Connectedness to an adjacent source of immigrants did not influence rat density within a fragment in either season (summer P = 0.25, autumn P = 0.67). An uncalibrated, rapid (one-night) index of ship rat density, using baited tracking tunnels set in a 50 Ă 50 m grid, showed a promising relationship with the number of rats killed per hectare over the first six nights, up to tracking index values of c. 30% (corresponding to c. 3â5 rats haâ1). The index will enable managers to determine if rat abundance is low enough to achieve conservation benefits. Our results confirm a dilemma for conservation in forest fragments. Fencing protects vegetation, litter and associated ecological processes, but also increases number of ship rats, which destroy seeds, invertebrates and nesting birds. Maximising the biodiversity values of forest fragments therefore requires both fencing and control of ship rats
Subtle Interactions and Electron Transfer between U-III, Np-III, or Pu-III and Uranyl Mediated by the Oxo Group
Calcutta Botanic Garden and the colonial re-ordering of the Indian environment
This article examines three hand-painted colour maps that accompanied the annual report of the Calcutta Botanic Garden for 1846 to illustrate how the Gardenâs layout, uses and functions had changed over the previous 30 years. The evolution of the Calcutta Botanic Garden in the first half of the nineteenth-century reflects a wider shift in attitudes regarding the relationship between science, empire and the natural world. On a more human level the maps result from, and illustrate, the development of a vicious personal feud between the two eminent colonial botanists charged with superintending the garden in the 1840s
How Good a Deal Was the Tobacco Settlement?: Assessing Payments to Massachusetts
We estimate the increment in Massachusetts Medicaid program costs attributable to smoking from December 20, 1991, to 1998. We describe how our methods improve upon earlier estimates of analogous costs at the national level. Current costs to the Massachusetts Medicaid program approximate the payments to Massachusetts under the tobacco settlement of November 1998. Whether these payments are viewed as appropriate compensation for Medicaid costs over time depends upon the rate of increase in future health care costs, the rate of decline in smoking, the proportion of smoking that should be attributed to the actions of the tobacco companies and the liklihood that state would have prevailed at trial. The costs to the Medicaid program are dwarfed by the internal costs to smokers themselves.
Patterns of Duality in N=1 SUSY Gauge Theories
We study the patterns in the duality of a wide class of N=1 supersymmetric
gauge theories in four dimensions. We present many new generalizations of the
classic duality models of Kutasov and Schwimmer, which have themselves been
generalized numerous times in works of Intriligator, Leigh and the present
authors. All of these models contain one or two fields in a two-index tensor
representation, along with fields in the defining representation. The
superpotential for the two-index tensor(s) resembles A_k or D_k singularity
forms, generalized from numbers to matrices. Looking at the ensemble of these
models, classifying them by superpotential, gauge group, and ``level'' -- for
terminology we appeal to the architecture of a typical European-style theatre
-- we identify emerging patterns and note numerous interesting puzzles.Comment: 34 pages, 4 figures, uses harvmac and table
MODIS airborne simulator visible and near-infrared calibration, 1991 FIRE-Cirrus field experiment. Calibration version: FIRE King 1.1
Calibration of the visible and near-infrared channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1991 FIRE-Cirrus field experiment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Laboratory tests during the FIRE Cirrus field experiment were conducted to calibrate the hemisphere and from the hemisphere to the MAS. The purpose of this report is to summarize the FIRE-Cirrus hemisphere calibration, and then describe how the MAS was calibrated from observations of the hemisphere data. All MAS calibration measurements are presented, and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. Thermal sensitivity of the MAS visible and near-infrared calibration is also discussed. Typically, the MAS in-flight is 30 to 60 degrees C colder than the room temperature laboratory calibration. Results from in-flight temperature measurements and tests of the MAS in a cold chamber are given, and from these, equations are derived to adjust the MAS in-flight data to what the value would be at laboratory conditions. For FIRE-Cirrus data, only channels 3 through 6 were found to be temperature sensitive. The final section of this report describes comparisons to an independent MAS (room temperature) calibration by Ames personnel using their 30-inch integrating sphere
Electroweak Baryogenesis in the Next to Minimal Supersymmetric Model
In the electroweak phase transition there arises the problem of baryon number
washout by sphaleron transitions, which can be avoided if the phase transition
is strongly enough first order. The minimal supersymmetric standard model has
just two Higgs doublets H1 and H2, while the next to minimal model, NMSSM, has
an additional singlet, N, this latter giving rise to the helpful feature that
the Higgs potential contains a tree level trilinear field term. We use the
tunneling criterion for the existence of a first order electroweak phase
change. A quantitative statistical analysis indicates that with parameters of
the NMSSM satisfying the experimental constraints a strong first order phase
change occurs in about 50% of cases.Comment: 15 pages, plain LaTe
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