1,336 research outputs found
A description of an automated database comparison program
An interactive FORTRAN computer comparison program designed to automatically locate regions of incongruity between two databases is described. The software, guided by user input parameters, incrementally compares the databases and generates plots of these regions in the databases which do not compare within a specified tolerance. Additionally, tools are provided within the software which enable the user to statistically reduce the number of data points in the databases compared. To facilitate the description of these tools, the procedures used to compare two aerodynamic databases for an F-18A fighter aircraft are detailed
Design and fabrication of solar cell modules
A program conducted for design, fabrication and evaluation of twelve silicon solar cell modules is described. The purpose of the program was to develop a module design consistent with the requirements and objectives of JPL specification and to also incorporate elements of new technologies under development to meet LSSA Project goals. Module development emphasized preparation of a technically and economically competitive design based upon utilization of ion implanted solar cells and a glass encapsulation system. The modules fabricated, tested and delivered were of nominal 2 X 2 foot dimensions and 20 watt minimum rating. Basic design, design rationale, performance and results of environmental testing are described
Gamma-ray lines and One-Loop Continuum from s-channel Dark Matter Annihilations
The era of indirect detection searches for dark matter has begun, with the
sensitivities of gamma-ray detectors now approaching the parameter space
relevant for weakly interacting massive particles. In particular, gamma ray
lines would be smoking gun signatures of dark matter annihilation, although
they are typically suppressed compared to the continuum. In this paper, we pay
particular attention to the 1-loop continuum generated together with the
gamma-ray lines and investigate under which conditions a dark matter model can
naturally lead to a line signal that is relatively enhanced. We study generic
classes of models in which DM is a fermion that annihilates through an
s-channel mediator which is either a vector or scalar and identify the coupling
and mass conditions under which large line signals occur. We focus on the
"forbidden channel mechanism" advocated a few years ago in the "Higgs in space"
scenario for which tree level annihilation is kinematically forbidden today.
Detailed calculations of all 1-loop annihilation channels are provided. We
single out very simple models with a large line over continuum ratio and
present general predictions for a large range of WIMP masses that are relevant
not only for Fermi and Hess II but also for the next generation of telescopes
such as CTA and Gamma-400. Constraints from the relic abundance, direct
detection and collider bounds are also discussed.Comment: 32 pages, 13 figures; v2: minor clarifications, summary paragraph
added; v3: matches published version, minor clarifications, results unchange
The Effects of Using iPads to Increase Basic Math Fact Automaticity
Our investigation was on the effects of using iPads to increase basic fact automaticity. We wanted to explore what strategy worked best to increase fact fluency: flashcards and paper/pencil practice or iPad practice. The project took place in one fourth-grade classroom and one fifth-grade classroom. The fourth-grade classroom had twenty-one students. The fifth-grade classroom had twenty-two students. We collected data with pretest and posttest instruments. We also collected data through weekly observations. Students using the iPads were also monitored using the Moby Max fact fluency program. The results indicated that daily flashcard and paper/pencil practice provided a higher rate of improvement of fact fluency on a two-minute test. We concluded that although the data does not indicate a higher rate of improvement by using iPads, other factors must also be included. One important factor was that the students who showed the greatest improvement also happened to be in the fifth-grade classroom. The implication for us is that we will use a combination of iPad practice along with the flashcard and paper/pencil review to increase student mathematics fluency
Controls, Displays, and Information Transfer for General Aviation IFR Operations
The purpose of the workshop was to review and evaluate the work performed under the NASA Single Pilot IFR (SPIFR) program, to highlight and disseminate major research findings, and to provide a forum for industry, universities, and government to interact and discuss the future thrust of research in the SPIFR program. The presentations selected represent key elements of the SPIFR program. These elements are classified into five disciplinary areas: program definition, controls, displays, information transfer, and research simulation facilities. Emphasis is also placed on aircraft accident investigation
Higgs ID at the LHC
We make a complete catalog of extended Higgs sectors involving SU(2)_L
doublets and singlets, subject to natural flavor conservation. In each case we
present the couplings of a light neutral CP-even Higgs state h in terms of the
model parameters, and identify which models are distinguishable in principle
based on this information. We also give explicit expressions for the model
parameters in terms of h couplings and exhibit the behaviors of the couplings
in the limit where the deviations from the Standard Model Higgs couplings are
small. Finally we discuss prospects for differentiation of extended Higgs
models based on measurements at the LHC and ILC and identify the regions in
which these experiments could detect deviations from the SM Higgs predictions.Comment: 46 pages, 6 figures, 2 tables, PRD versio
Theory Building as Integrated Reflection: Understanding Physician Reflection Through Human Communication Research, Medical Education, and Ethics
Grounded in a presupposition that a single explanatory framework cannot fully account for the expansive learning processes that occur during medical residency, the article examines developing physicians’ reflective writing from three disciplinary lenses. The goal is to understand how the multi-dimensional nature of medical residency translates into assembling educational experiences and constructing meaning that cannot be fully explained through a single discipline. An interdisciplinary research team across medical education, communication, and ethics qualitatively analyzed reflective entries (N=756) completed by family medicine residents (N=33) across an academic year. Results provide evidence for moving toward an integrated thematic explanation across disciplines. The authors suggest that the integration of disciplinary explanations allows for comprehensive understanding of reflection as a cornerstone in the broader formation of the physician. Examples provide evidence for an integrated understanding of a fuller human experience by considering the three thematic explanations as co-occurring, reciprocal processes
The WIMP Forest: Indirect Detection of a Chiral Square
The spectrum of photons arising from WIMP annihilation carries a detailed
imprint of the structure of the dark sector. In particular, loop-level
annihilations into a photon and another boson can in principle lead to a series
of lines (a WIMP forest) at energies up to the WIMP mass. A specific model
which illustrates this feature nicely is a theory of two universal extra
dimensions compactified on a chiral square. Aside from the continuum emission,
which is a generic prediction of most dark matter candidates, we find a
"forest" of prominent annihilation lines that, after convolution with the
angular resolution of current experiments, leads to a distinctive (2-bump plus
continuum) spectrum, which may be visible in the near future with the Fermi
Gamma-Ray Space Telescope (formerly known as GLAST).Comment: 11 pages, 4 figure
254Digene hybrid capture (DHC) CMV DNA assay compared to CMV culture and incidence of CMV disease in allogeneic hematopoietic stem cell transplantation (ASCT)
- …