2,777 research outputs found
Computer program for stresses and buckling of heated composite-stiffened panels and other structures (BUCLASP 3)
General-purpose program is intended for thermal stress and instability analyses of structures such as axially-stiffened curved panels. Two types of instability analyses can be effected by program: (1) thermal buckling with temperature variation as specified and (2) buckling due to in-plane biaxial loading
Threat expert system technology advisor
A prototype expert system was developed to determine the feasibility of using expert system technology to enhance the performance and survivability of helicopter pilots in a combat threat environment while flying NOE (Nap of the Earth) missions. The basis for the concept is the potential of using an Expert System Advisor to reduce the extreme overloading of the pilot who flies NOE mission below treetop level at approximately 40 knots while performing several other functions. The ultimate goal is to develop a Threat Expert System Advisor which provides threat information and advice that are better than even a highly experienced copilot. The results clearly show that the NOE pilot needs all the help in decision aiding and threat situation awareness that he can get. It clearly shows that heuristics are important and that an expert system for combat NOE helicopter missions can be of great help to the pilot in complex threat situations and in making decisions
BUCLAP2: A computer program for instability analysis of laminated long plates subjected to combined inplane loads. User's manual
The usage of the computer program BUCLAP2 is described. The program is intended for linear instability analysis of long, rectangular flat and curved laminated plates with arbitrary orientation of orthotropic axes in each layer. The loadings considered are combinations of inplane normal and shear loads. Arbitray elastic boundary conditions are included for the sides of the plate Instructions for use of the program are included along with Input data requirements, output information, and sample problems. For program description, see
Engaging And Enacting Writing In First-year Composition: Re-imagining Student Self-efficacy In Writing
According to educational theory, learning to write necessitates self-belief that one is capable of performing required tasks. This belief is called self-efficacy, a component of human agency. Students who enter First-Year Composition (FYC), are often unaware of the writing challenges that lie ahead, and many educational psychologists posit that self-efficacy beliefs are the most important factor in meeting these writing challenges. While socio-cognitive theory shapes views of self-efficacy in education literature, to date, measures of self-efficacy in writing have focused only on the individual cognitive beliefs as they influence writing performance outcomes. However, current research in writing studies as well as posthuman theories of agency point to a broader, more contextually-bound view of agency for writing as emergent and enacted in socially constructed systems. This dissertation challenges the current view of self-efficacy as it is described in the educational literature as well as the ways in which self-efficacy in writing is measured, suggesting instead that self-efficacy beliefs and learning to write are deeply contextualized. In this dissertation, I examine student self-efficacy in writing using the lens of activity theory, not only as a set of stated individual beliefs but also as belief-in-action measured as images on writing maps, subtle shifts in language and talk about writing, as well as changes in writing practices. More importantly, I examine the agency that is constructed in the social system of FYC classrooms which may only later become internalized individual beliefs about abilities to write. My study suggests that self-efficacy beliefs are not bound by inside the head as belief about performing certain rules for writing, but instead self-efficacy beliefs about writing are emergent and enacted and bound to particular writing systems. Lingering feelings of agency for iii working in particular systems can move with students to similar systems; however, strong beliefs about writing as fixed and rule-bound can actually hinder how much students learn in FYC. The evidence suggests that self-efficacy in writing may be better theorized as writing efficacy, emergent agency for writing that strengthens as participants become engaged in working toward the motives of a writing system
Comparison of Energy Analysis Platforms for Title 24Compliance
The 2013 Building Energy Efficiency Standards for Low-Rise Residential Buildings allow users to demonstrate compliance via two methods: performance or prescriptive. Prescriptive documentation requires analysis to be conducted by-hand while performance compliance utilizes computer modeling software to analyze trade-offs, and demonstrate compliance through alternative building design parameters. Typically computer demonstrated compliance via the performance method is the most popular choice because it allows for complex buildings to be analyzed using their actual metrics which results in a more accurate report of proposed energy consumption (Ross, 2016). This method however requires additional software outside of the tools that architects and designers are already utilizing to create their working designs and construction documents. The purpose of this paper is to give an overview of both compliance methods and the three approved software packages and then compare and contrast one of the most popular BIM software package, Autodesk Revit, with the documentation required to demonstrate compliance with the Building Energy Efficiency standard to access whether the two could be integrated in future to create one platform for design, analytics and documentation
Probing the IGM/Galaxy Connection IV: The LCO/WFCCD Galaxy Survey of 20 Fields Surrounding UV Bright Quasars
We publish the survey for galaxies in 20 fields containing ultraviolet bright
quasars (with z_em 0.1 to 0.5) that can be used to study the association
between galaxies and absorption systems from the low-z intergalactic medium
(IGM). The survey is magnitude limited (R~19.5 mag) and highly complete out to
10' from the quasar in each field. It was designed to detect dwarf galaxies (L
~ 0.1 L*) at an impact parameter rho 1Mpc (z=0.1) from a quasar. The complete
sample (all 20 fields) includes R-band photometry for 84718 sources and
confirmed redshifts for 2800 sources. This includes 1198 galaxies with 0.005 <
z < (z_em - 0.01) at a median redshift of 0.18, which may associated with IGM
absorption lines. All of the imaging was acquired with cameras on the Swope 40"
telescope and the spectra were obtained via slitmask observations using the
WFCCD spectrograph on the Dupont 100" telescope at Las Campanas Observatory
(LCO). This paper describes the data reduction, imaging analysis, photometry,
and spectral analysis of the survey. We tabulate the principal measurements for
all sources in each field and provide the spectroscopic dataset online.Comment: Accepted to the Astrophysical Journal Supplements; 20 pages, only 6
figures shown in this version. See
http://www.ucolick.org/~xavier/WFCCDOVI/index.html for a full-length
manuscript and other supportive materia
Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 6: IPAD system development and operation
The strategy of the IPAD implementation plan presented, proposes a three phase development of the IPAD system and technical modules, and the transfer of this capability from the development environment to the aerospace vehicle design environment. The system and technical module capabilities for each phase of development are described. The system and technical module programming languages are recommended as well as the initial host computer system hardware and operating system. The cost of developing the IPAD technology is estimated. A schedule displaying the flowtime required for each development task is given. A PERT chart gives the developmental relationships of each of the tasks and an estimate of the operational cost of the IPAD system is offered
The effects of multiple aerospace environmental stressors on human performance
An extended Fitt's law paradigm reaction time (RT) task was used to evaluate the effects of acceleration on human performance in the Dynamic Environment Simulator (DES) at Armstrong Laboratory, Wright-Patterson AFB, Ohio. This effort was combined with an evaluation of the standard CSU-13 P anti-gravity suit versus three configurations of a 'retrograde inflation anti-G suit'. Results indicated that RT and error rates increased 17 percent and 14 percent respectively from baseline to the end of the simulated aerial combat maneuver and that the most common error was pressing too few buttons
The sexual health needs of looked after young people; findings from qualitative interviews led through public health and health psychology.
Background - Looked after young people (LAYP) have poorer sexual health outcomes than their peers. However, research seldom examines the health needs of, or intervenes with, this group. The aim of the current study was to identify LAYP's perceived sexual health needs and explore sources of sexual health information, knowledge levels, concerns and service preferences.
Methods - Looked after young people within Fife, Scotland, were recruited through their workers and carers to participate in qualitative semi-structured interviews. Those aged 12–19 years were targeted for recruitment. National Health Services ethics approval was granted. Thematic analysis was conducted using NVivo.
Results - Interviews were conducted with 10 LAYP. Key themes included gaps in knowledge, and gaps between knowledge and behaviour. Being ‘looked after’ may have negative consequences on knowledge, sources of support and safer sex. A flexible, one-to-one service, aimed at several lifestyle issues, not solely sexual health, was preferred by respondents.
Conclusion - Looked after young people require support to bridge the gap between knowledge and behaviour and several theories relevant to the findings have been identified. Participants desired more support around a range of health issues, which may come from school, workers and carers, as well as health professionals. Further research examining effective interventions with this group is crucial to improve outcomes
A Sub-Damped Ly Absorber with Unusual Abundances: Evidence of Gas Recycling in a Low-Redshift Galaxy Group
Using Hubble Space Telescope/Space Telescope Imaging Spectrograph G140M
spectroscopy, we investigate an absorption-line system at =0.07489 in the
spectrum of the quasi-stellar object PG 1543+489 (=0.401). The
sightline passes within kpc of an edge-on disk galaxy at a
similar redshift, but the galaxy belongs to a group with four other galaxies
within kpc. We detect H I [log (H I/) = 19.120.04]
as well as N I, Mg II, Si II, and Si III, from which we measure a gas-phase
abundance of [N/H] = . Photoionization models indicate that the
nitrogen-to-silicon relative abundance is solar, yet magnesium is underabundant
by a factor of 2. We also report spatially resolved emission-line
spectroscopy of the nearby galaxy, and we extract its rotation curve. The
galaxy's metallicity is higher than [N/H] in the absorber,
and interestingly, the absorber velocities suggest that the gas at 66
kpc is corotating with the galaxy's stellar disk, possibly with an inflow
component. These characteristics could indicate that this sub-damped Ly
absorber system arises in a "cold-accretion" flow. However, the absorber
abundance patterns are peculiar. We hypothesize that the gas was ejected from
its galaxy of origin (or perhaps is a result of tidal debris from interactions
between the group galaxies) with a solar nitrogen abundance, but that
subsequently mixed with (and was diluted by) gas in the circumgalactic medium
(CGM) or group. If the gas is bound to the nearby galaxy, this system may be an
example of the gas "recycling" predicted by theoretical galaxy simulations. Our
hypothesis is testable with future observations.Comment: 16 pages (in print): The Astrophysical Journal, vol 872, 12
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