11,550 research outputs found
NASA metric system study
Statistical analysis of metric and English unit usage and trends in technical documents generated by NASA Center
Technology utilization program report, 1974
The adaptation of various technological innovations from the NASA space program to industrial and domestic applications is summarized
Mechanisms of wave transformation in finite-depth water
Mechanisms of wave transformation in finite-depth water are investigated. The linear mechanisms ex- amined are percolation, bottom motion, shoaling, and refraction. The nonlinear mechanisms examined are wave-wave interaction and bottom friction. New exact computations of the nonlinear transfer for fi- nite-depth waves are presented for some directional wave spectra. These mechanisms are found to ex- plain satisfactorily wave decay observations obtained at several sites with different bottom sediment properties. The decay rates at these sites are found to be dominated by different mechanisms which are determined by the bottom conditions. As an example, detailed calculations are presented for data ob- tained at the Jonswap site
Resolving Structure in Human Brain Organization: Identifying Mesoscale Organization in Weighted Network Representations
Human brain anatomy and function display a combination of modular and
hierarchical organization, suggesting the importance of both cohesive
structures and variable resolutions in the facilitation of healthy cognitive
processes. However, tools to simultaneously probe these features of brain
architecture require further development. We propose and apply a set of methods
to extract cohesive structures in network representations of brain connectivity
using multi-resolution techniques. We employ a combination of soft
thresholding, windowed thresholding, and resolution in community detection,
that enable us to identify and isolate structures associated with different
weights. One such mesoscale structure is bipartivity, which quantifies the
extent to which the brain is divided into two partitions with high connectivity
between partitions and low connectivity within partitions. A second,
complementary mesoscale structure is modularity, which quantifies the extent to
which the brain is divided into multiple communities with strong connectivity
within each community and weak connectivity between communities. Our methods
lead to multi-resolution curves of these network diagnostics over a range of
spatial, geometric, and structural scales. For statistical comparison, we
contrast our results with those obtained for several benchmark null models. Our
work demonstrates that multi-resolution diagnostic curves capture complex
organizational profiles in weighted graphs. We apply these methods to the
identification of resolution-specific characteristics of healthy weighted graph
architecture and altered connectivity profiles in psychiatric disease.Comment: Comments welcom
Physics of Single-Top Quark Production at Hadron Colliders
We discuss the physics of single-top quark production and decay at hadron
colliders, such as the Tevatron, the \tevstar~and the LHC. Our study includes
how to measure the mass and the width of the top quark produced from a
{\hbox{single-}} or a single- process. We also show how to probe new
physics by studying the couplings of -- and show what can be
improved from measuring the production rate of single-top events. We also
discuss how to probe CP properties of the top quark by measuring the single-top
production rate. Finally, we present a Monte Carlo study on the detection of
single-top events in hadron collisions.Comment: Thesis, 102 pages, Latex, needs 45 figures (not included). All Tex
files and the associated analysis package ONETOP may be obtained via
anonymous ftp at ftp://cteq14.pa.msu.edu/pub/carlson_d
A Characterization of the Inorganic and Available Phosphorus Content of Four South Dakota Soils
Phosphorus is an element that is becoming increasingly important in South Dakota soils. Although there seems to be a large supply of inorganic phosphorus in these soils, its availability to crops is definitely restricted. It was thought that a knowledge of the distribution of the different forms of phosphorus over a range of South Dakota soils is a necessary background for further understand phosphorus problems in the state. Interpretation of phosphorus behavior in soils involves some of the most interesting and baffling problems in the realm of soil science. Soils have been characterized by determining many parameters such as the pH, the clay content, the cation exchange capacity, and exchangeable cases. It was the purpose of this research to characterize the South Dakota soils studied as to the amount of phosphorus present as aluminum, iron, and calcium phosphate respectively, and to determine the phosphate release patterns of these soils, as indicated by successive leachings
Experimental and Theoretical Determination of Forces and Moments on a Store and on a Store- Pylon Combination Mounted on a 45 Deg Swept- Wing-Fuselage Configuration at a Mach Number of 1.61
Forces and moments of store-pylon combination mounting on swept wing-fuselage configuration in supersonic pressure tunne
Towards a relation extraction framework for cyber-security concepts
In order to assist security analysts in obtaining information pertaining to
their network, such as novel vulnerabilities, exploits, or patches, information
retrieval methods tailored to the security domain are needed. As labeled text
data is scarce and expensive, we follow developments in semi-supervised Natural
Language Processing and implement a bootstrapping algorithm for extracting
security entities and their relationships from text. The algorithm requires
little input data, specifically, a few relations or patterns (heuristics for
identifying relations), and incorporates an active learning component which
queries the user on the most important decisions to prevent drifting from the
desired relations. Preliminary testing on a small corpus shows promising
results, obtaining precision of .82.Comment: 4 pages in Cyber & Information Security Research Conference 2015, AC
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