34,535 research outputs found
High power-high voltage waterload Patent
Variable water load for dissipating large amounts of electrical power during high voltage power supply test
Trap Response of Michigan Social Wasps (Hymenoptera: Vespidae) to the Feeding Attractants Acetic Acid, Isobutanol, and Heptyl Butyrate.
Nine species of social wasps were captured in traps baited with acetic acid, isobutanol, heptyl butyrate and combinations of acetic acid and either isobutanol or heptyl butyrate. Three yellowjacket species in the Vespula rufa species group were captured in traps (Vespula acadica (Sladen), Vespula consobrina (Saussure), Vespula vidua (Saussure)). They responded similarly, with attraction only to heptyl butyrate. Three yellowjacket species in the Vespula vulgaris species group were also captured in traps (Vespula vulgaris (L.), Vespula flavorpilosa Jacobson, Vespula maculifrons (Buyyson)). They responded similarly, with attraction primarily to the combination of acetic acid and isobutanol. The bald-faced hornet, Dolichovespula maculata (L.), was attracted to acetic acid and was more strongly attracted to the combination of acetic acid and isobutanol. The aerial yellowjacket, Dolichovespula arenaria (Fabr.), was attracted to isobutanol, and was more strongly attracted to the combination of acetic acid and isobutanol. These results add to our understanding of how to target various species of social wasps with chemical lures
“I had no control over myself or my education”: mainstream school refusal from the perspectives of young people on the autism spectrum.
Young people on the autism spectrum are more likely to experience school refusal than their neurotypical peers. However, research is dominated by the neurotypical experience and where autism is directly addressed, it is done so from the perspective of parents or professionals. By hearing from young people on the autism spectrum about their school refusal, it is hoped that this study is an early step in redressing the imbalance seen so far. This qualitative study, built on a social constructivist and communitarian paradigm, which views participants as experts, utilised online conferencing software to record parent-child conversations about their school refusal experiences. Participants were four young people on the autism spectrum between the ages of 10-18, who have experienced school refusal in a mainstream setting in one Local Authority in the South of England. The heterogeneous nature of school refusal is widely accepted; however, the School Environment, Peer Relationships and Teacher Relationships have emerged as dominant themes for participants when explored through the lens of school based factors, which this thesis focussed upon. Conclusions show that the influencing factors for school refusal identified by students on the autism spectrum include student-teacher relationships, being both listened to and heard by staff and peers, the values of the school system and ultimately the overwhelming culmination of factors at play. Framed through personal anecdotes, emotional responses and mental health reactions (such as anxiety and depression), participants demonstrated the very personal nature of school refusal. Recommendations include further research with an emphasis on student voice and participation, teacher training which contains examples of effective and positive working relationships with students on the autism spectrum, the early identification of risk factors, and a call for changes to academic outcomes as the single measure of schools
The NASA/industry Design Analysis Methods for Vibrations (DAMVIBS) program: Boeing Helicopters airframe finite element modeling
Mathematical models based on the finite element method of structural analysis, as embodied in the NASTRAN computer code, are routinely used by the helicopter industry to calculate airframe static internal loads used for sizing structural members. Historically, less reliance has been placed on the vibration predictions based on these models. Beginning in the early 1980's NASA's Langley Research Center initiated an industry wide program with the objective of engendering the needed trust in vibration predictions using these models and establishing a body of modeling guides which would enable confident future prediction of airframe vibration as part of the regular design process. Emphasis in this paper is placed on the successful modeling of the Army/Boeing CH-47D which showed reasonable correlation with test data. A principal finding indicates that improved dynamic analysis requires greater attention to detail and perhaps a finer mesh, especially the mass distribution, than the usual stress model. Post program modeling efforts show improved correlation placing key modal frequencies in the b/rev range with 4 percent of the test frequencies
The Inland Empire in 2015
Presents projections for international and local migration, demographics, education, economic and employment conditions, and political participation for Southern California's Riverside and San Bernardino counties
Study of boundary-layer transition using transonic-cone preston tube data
The laminar boundary layer on a 10 degree cone in a transonic wind tunnel was studied. The inviscid flow and boundary layer development were simulated by computer programs. The effects of pitch and yaw angles on the boundary layer were examined. Preston-tube data, taken on the boundary-layer-transition cone in the NASA Ames 11 ft transonic wind tunnel, were used to develope a correlation which relates the measurements to theoretical values of laminar skin friction. The recommended correlation is based on a compressible form of the classical law-of-the-wall. The computer codes successfully simulates the laminar boundary layer for near-zero pitch and yaw angles. However, in cases of significant pitch and/or yaw angles, the flow is three dimensional and the boundary layer computer code used here cannot provide a satisfactory model. The skin-friction correlation is thought to be valid for body geometries other than cones
Distant perturbation asymptotics in window-coupled waveguides. I. The non-threshold case
We consider a pair of adjacent quantum waveguides, in general of different
widths, coupled laterally by a pair of windows in the common boundary, not
necessarily of the same length, at a fixed distance. The Hamiltonian is the
respective Dirichlet Laplacian. We analyze the asymptotic behavior of the
discrete spectrum as the window distance tends to infinity for the generic
case, i.e. for eigenvalues of the corresponding one-window problems separated
from the threshold
The role of regulatory mechanisms for control of plant diseases and food security — case studies from potato production in Britain
Being aware of the potentially devastating impacts of plant diseases on food security, governments have designed and employ plant health legislation to prevent or inhibit the worst impacts. The development of such policies in Britain, and latterly in Europe, can be closely linked to disease events that have occurred in the potato sector. We analyse early and current examples of policies governing potato diseases in Britain to identify the decision processes leading to the implementation of such phytosanitary policies and how they have evolved over time and in response to different disease threats. Reasons for developing and implementing phytosanitary policies include the desire to prevent pathogens being introduced (entering and establishing in a new area), the protection of export markets, and the lack of effective control measures. Circumstances in which regulatory policies would not be appropriate could include situations where a disease is already widely distributed, unacceptable costs, lack of exclusion measures, or difficulties of disease diagnosis. We conclude that in general, government policies have worked well in protecting British potato growing over the last one hundred years, despite of the failures of some of the policies discussed here. They have also contributed much to the development of plant health policies for other crops. Voluntary grower initiatives are a new mechanism complementing existing formal policies with an additional level of security that allows individual growers to take on additional responsibility rather than relying entirely on government legislation
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