364 research outputs found
Airport-Noise Levels and Annoyance Model (ALAMO) user's guide
A guide for the use of the Airport-Noise Level and Annoyance MOdel (ALAMO) at the Langley Research Center computer complex is provided. This document is divided into 5 primary sections, the introduction, the purpose of the model, and an in-depth description of the following subsystems: baseline, noise reduction simulation and track analysis. For each subsystem, the user is provided with a description of architecture, an explanation of subsystem use, sample results, and a case runner's check list. It is assumed that the user is familiar with the operations at the Langley Research Center (LaRC) computer complex, the Network Operating System (NOS 1.4) and CYBER Control Language. Incorporated within the ALAMO model is a census database system called SITE II
Designing and specifying mobility within the multiagent systems engineering methodology
Recently, researchers have created many platforms and applications for mobile agents; however, current Agent-Oriented Software Engineering (AOSE) methodologies have yet not fully integrated the unique properties of these mobile agents. This paper attempts to bridge the gap between current AOSE methodologies and mobile agent systems by incorporating mobility into the established Multiagent Systems Engineering (MaSE) methodology. We accomplished this by adding a move command to the MaSE analysis models and then defined the required transformations to incorporate the required functionality into the design. Finally, we translated the design models into Java-based agents that operate within a mobile agent environment. 1
A Practical Methodology for Quantifying Random and Systematic Components of Unexplained Variance in a Wind Tunnel
This paper documents a check standard wind tunnel test conducted in the Langley 0.3-Meter Transonic Cryogenic Tunnel (0.3M TCT) that was designed and analyzed using the Modern Design of Experiments (MDOE). The test designed to partition the unexplained variance of typical wind tunnel data samples into two constituent components, one attributable to ordinary random error, and one attributable to systematic error induced by covariate effects. Covariate effects in wind tunnel testing are discussed, with examples. The impact of systematic (non-random) unexplained variance on the statistical independence of sequential measurements is reviewed. The corresponding correlation among experimental errors is discussed, as is the impact of such correlation on experimental results generally. The specific experiment documented herein was organized as a formal test for the presence of unexplained variance in representative samples of wind tunnel data, in order to quantify the frequency with which such systematic error was detected, and its magnitude relative to ordinary random error. Levels of systematic and random error reported here are representative of those quantified in other facilities, as cited in the references
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Modeling changes in mineral assemblages and sorptive capacity within the altered zone: analytical data for flow-through experiment
Mineral changes that may occur within the altered zone (AZ) will develop in response to complex interactions among condensate, pore waters, fracture mineralogy, and the mineralogy of the in situ rocks. At the Yucca Mountain site, the mineralogy of the in situ rock varies from one lithologic unit to another, reflecting different initial bulk rock chemistries and different degrees of devitrification and welding. To account for these variations when describing the possible changes the potential repository block will experience during heating and fluid movement, a credible database of experimental results describing the chemical and mineralogical consequences of rock-water interaction must be available; against this, modeling capabilities are compared. Once the capability is established to accurately simulate the time-dependent evolution of rock-water systems at elevated temperatures, confidence can be placed in models of the mineral changes expected within the AZ. This report describes experiments and modeling that consider the effects of different starting materials on mineral evolution and on the rates of mineral formation. Bounds are placed on the kinetics of the controlling dissolution-rate constants, which are the fundamental parameters that influence secondary mineral development. The sensitivity of the results to different secondary minerals is considered in the simulations. The most significant parameters affecting the results are shown to be the effective surface areas of the phases involved, the rate constants for the phases, and, for the case of vitric material, the model used for glass dissolution
Space Shuttle Debris Impact Tool Assessment Using the Modern Design of Experiments
Complex computer codes are used to estimate thermal and structural reentry loads on the Shuttle Orbiter induced by ice and foam debris impact during ascent. Such debris can create cavities in the Shuttle Thermal Protection System. The sizes and shapes of these cavities are approximated to accommodate a code limitation that requires simple "shoebox" geometries to describe the cavities -- rectangular areas and planar walls that are at constant angles with respect to vertical. These approximations induce uncertainty in the code results. The Modern Design of Experiments (MDOE) has recently been applied to develop a series of resource-minimal computational experiments designed to generate low-order polynomial graduating functions to approximate the more complex underlying codes. These polynomial functions were then used to propagate cavity geometry errors to estimate the uncertainty they induce in the reentry load calculations performed by the underlying code. This paper describes a methodological study focused on evaluating the application of MDOE to future operational codes in a rapid and low-cost way to assess the effects of cavity geometry uncertainty
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Gas sampling in the DST
Characterization of the rock-fluid interactions in the DST will play an important role in understanding the performance of waste package materials and radionuclide transport through the altered zone of a repository. Consequently, the chemistry of fluids and gases originating in the pore space of the rock and the changing compositions observed with time and temperature will be targeted for study in the chemistry boreholes of the DST. The chemical holes have been lined with SEAMIST (Science Engineering Associate Membrane In situ Sampling Technology) liners that allow gas and fluid from the pore spaces of the rock walls to be sampled on-site periodically. The concentrations of certain chemical species in the gases and fluids sampled at those locations will then be analyzed back in the laboratory. The baseline sampling of the rock-pore gases (prior to heater turn- on) is described
Individually Unique Body Color Patterns in Octopus (Wunderpus photogenicus) Allow for Photoidentification
Studies on the longevity and migration patterns of wild animals rely heavily on the ability to track individual adults. Non-extractive sampling methods are particularly important when monitoring animals that are commercially important to ecotourism, and/or are rare. The use of unique body patterns to recognize and track individual vertebrates is well-established, but not common in ecological studies of invertebrates. Here we provide a method for identifying individual Wunderpus photogenicus using unique body color patterns. This charismatic tropical octopus is commercially important to the underwater photography, dive tourism, and home aquarium trades, but is yet to be monitored in the wild. Among the adults examined closely, the configurations of fixed white markings on the dorsal mantle were found to be unique. In two animals kept in aquaria, these fixed markings were found not to change over time. We believe another individual was photographed twice in the wild, two months apart. When presented with multiple images of W. photogenicus, volunteer observers reliably matched photographs of the same individuals. Given the popularity of W. photogenicus among underwater photographers, and the ease with which volunteers can correctly identify individuals, photo-identification appears to be a practical means to monitor individuals in the wild
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An analysis of state laws designed to effect economic control of the market milk industry
Stimulated radiative laser cooling
Building a refrigerator based on the conversion of heat into optical energy
is an ongoing engineering challenge. Under well-defined conditions, spontaneous
anti-Stokes fluorescence of a dopant material in a host matrix is capable of
lowering the host temperature. The fluorescence is conveying away a part of the
thermal energy stored in the vibrational oscillations of the host lattice. In
particular, applying this principle to the cooling of (solid-state) lasers
opens up many potential device applications, especially in the domain of
high-power lasers. In this paper, an alternative optical cooling scheme is
outlined, leading to radiative cooling of solid-state lasers. It is based on
converting the thermal energy stored in the host, into optical energy by means
of a stimulated nonlinear process, rather than a spontaneous process. This
should lead to better cooling efficiencies and a higher potential of applying
the principle for device applications
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