7,662 research outputs found
Integrated voice and visual systems research topics
A series of studies was performed to investigate factors of helicopter speech and visual system design and measure the effects of these factors on human performance, both for pilots and non-pilots. The findings and conclusions of these studies were applied by the U.S. Army to the design of the Army's next generation threat warning system for helicopters and to the linguistic functional requirements for a joint Army/NASA flightworthy, experimental speech generation and recognition system
The relationship between food intake and predation risk in migratory caribou and implications to caribou and wolf population dynamics
We examined the hypothesis that spring migration in barren-ground caribou (Rangifer tarandus) enhances access to high quality food, reduces predation risks or both. We related our findings to the hypothesis that one of the consequences of migration is that prey populations cannot be regulated by predation because predators are unable to respond numerically to changes in abundance of migratory prey. In the Northwest Territories, migration to calving grounds by pregnant cows reduced the risk of predation on neonates. Wolf (Canis lupus) densities on calving grounds averaged only 22% of winter range densities because most wolves denned near tree line. The quality and quantity of food that was available to cows that migrated to calving grounds was lower than for bulls and other caribou that lagged far behind the pregnant cows during spring migration. Fecal nitrogen levels were higher in bulls than in cows in late May and early June but there were no differences in mid or late June. Areas occupied by bulls in late May had a greater biomass of live sedges than on the calving ground in early June. It appears that although food in July is abundant and nutritious, insect harassment prevents efficient feeding. Body fat reserves in both sexes declined to almost zero by mid-July, the lowest level of the year. Insect numbers declined in August and body fat levels increased to the highest level of the year by early September. Because the timing of caribou's return to the hunting ranges of tree line denning wolves was related to caribou density, our data were inconsistent with the suggested consequence of migration. Tree line denning by wolves and density-dependent changes in caribou migration suggests a mechanism for population regulation in caribou and wolves. We suggest that the process is as follows; when caribou numbers increase, some density-dependent factor causes range expansion in August (e.g., competition for food) causing caribou to return earlier to the hunting ranges of tree line denning wolves, more denning wolves have access to caribou, wolf pup survival increases and wolf numbers increase. The effect on caribou population growth will depend on the timing and magnitude of the wolf numerical response
Minimum Out-of-Slice Error SMS RF Pulse Design with Direct Peak, Power, and In-Slice Error Constraints
No abstract available
Survey of 1985 Periodical Cicada (Homoptera: Magicicada) Emergence Sites in Washington County, Arkansas, With Reference to Ecological Implications
Systematic roadside surveys were conducted in June 1985 in Washington County, Arkansas, to locate areas where 13-year periodical cicadas had emerged during May. Although cicadas were found in a variety of upland and bottom land forest habitats, the present cicada distribution reflects the original forest and prairie pattern in the county, even though those boundaries are now largely lost. This suggests a high degree of philopatry whereby emergency areas have remained in the same area for the last 100 years. All present day emergence areas are within the White River drainage, suggesting that it was the main cicada dispersal route into northwestern Arkansas. It now probably marks the western limit of Brood XIX in northwestern Arkansas
An Assessment Framework for First-Year Introduction to Engineering Courses
In this evidence-based practice paper, we describe an assessment framework that applies to first-year introductory engineering courses. First-year engineering courses cover a variety of learning objectives that address both technical and professional outcomes outlined in ABET. These courses also often involve open-ended design and modeling projects. The assessment of multiple competencies along with open-ended design can be a challenging task for educators. In this paper, we describe a framework that guides instructional processes for effective assessment for student learning. This assessment-centered teaching and learning framework helps connect specific learning objectives to broader learning goals or competencies and on-going formative feedback targeting student progression on specific learning objectives. Our plan is to refine the framework using a design-based research approach. Following the description of the model and its development, we present results from the first cycle of implementation. We conclude by discussing hybrid ways for combining traditional methods of assessment with the ability to highlight performance expectations and the appropriate uses of the framework in the classroom
Intertrial unconditioned stimuli differentially impact trace conditioning
Three experiments assessed how appetitive conditioning in rats changes over the duration of a trace conditioned stimulus (CS) when unsignaled unconditioned stimuli (USs) are introduced into the intertrial interval. In Experiment 1, a target US occurred at a fixed time either shortly before (embedded), shortly after (trace), or at the same time (delay) as the offset of a 120-s CS. During the CS, responding was most suppressed by intertrial USs in the trace group, less so in the delay group, and least in the embedded group. Unreinforced probe trials revealed a bell-shaped curve centered on the normal US arrival time during the trace interval, suggesting that temporally-specific learning occurred both with and without intertrial USs. Experiments 2a and 2b confirmed that the bulk of the trace CS became inhibitory when intertrial USs were scheduled, as measured by summation and retardation tests, even though CS offset evoked a temporally precise conditioned response. Thus, an inhibitory CS may give rise to new stimuli specifically linked to its termination, which were excitatory. A modification to the micostimulus temporal difference model is offered to account for the data
Giant Alcohol: A Worthy Opponent for the Children of the Band of Hope
From its foundation in 1847, the temperance organisation the Band of Hope addressed its young members as consumers, victims, and agents. In the first two roles they encountered the effects of drink of necessity, but in the third role they were encouraged to seek it out, attempting to influence individuals and wider society against 'Giant Alcohol'.
With an estimated membership of half the school-age population by the early twentieth century, well over three million, the Band of Hope also acted more directly to influence policy, and encouraged young people to consider issues of policy and politics. With its wide range of activities and material to educate, entertain and empower millions of children, and its radical view of the place of the child, the Band of Hope not only mobilised its child members to lobby for legal change, including prohibition, but took an active part in pointing out the cost of alcohol to society, particularly during the 14-18 war. The organisation began to decline post 1918, and this paper focuses on the address made to children by the Band of Hope in the late nineteenth and early twentieth centuries, at a time when its innovative view of children as able to understand and influence policy decisions reflected developments in the construction of childhood. This article draws on the archive of the British National Temperance League, over 50,000 items located in the Livesey Collection, University of Central Lancashire
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