18,643 research outputs found
User friendly database for Neptune planetary radio astronomy observations
Planetary Radio Astronomy (PRA) data from the Voyager Neptune encounter were cleaned and reformatted in a variety of formats. Most of these formats are new and have been specifically designed to provide easy access and use of the data without the need to understand esoteric characteristics of the PRA instrument or the Voyager spacecraft. Several data sets were submitted to the Planetary Data System (PDS) and have either appeared already on peer reviewed CDROM's or are in the process of being reviewed for inclusion in forthcoming CD-ROM's. Many of the data sets are also available online electronically through computer networks; it is anticipated that as time permits, the PDS will make all the data sets that were a part of this contract available both online and on CD-ROM's
`Electronic Publishing' -- Practice and Experience
Electronic Publishing -- Origination, Dissemination and Design (EP-odd) is an academic journal which publishes refereed papers in the subject area of electronic publishing. The authors of the present paper are, respectively, editor-in-chief, system software consultant and senior
production manager for the journal. EP-odd's policy is that editors, authors, referees and production staff will work closely together using electronic mail. Authors are also encouraged to originate their
papers using one of the approved text-processing packages together with the appropriate set of macros which enforce the layout style for the journal. This same software will then be used by the
publisher in the production phase. Our experiences with these strategies are presented, and two recently developed suites of software are described: one of these makes the macro sets available over
electronic mail and the other automates the flow of papers through the refereeing process. The decision to produce EP-odd in this way means that the publisher has to adopt production procedures
which differ markedly from those employed for a conventional journal
A Note on Adult Overwintering of Dasymutilla Nigripes in Michigan (Hymenoptera: Mutillidae)
Excerpt: Although Dasymutilla nigripes (Fabricius) is one of the more common Michigan velvet ant species, little is known about its life cycle. In his summary of mutillid life cycles, Michel (1928) indicated that mutillids of northern latitudes probably overwinter in the prepupal stage within the subterranean cells of their hymenopterous hosts. Bohart and McSwain (1939) cited prepupal overwintering as normal for Dasymutilla sackenii (Cresson) in California. However, Potts and Smith (1944), also working in California, collected overwintering adult female Dasymutilla aureola pacifica (Cresson)
Subfactor realisation of modular invariants
We study the problem of realising modular invariants by braided subfactors
and the related problem of classifying nimreps. We develop the fusion rule
structure of these modular invariants. This structure is useful tool in the
analysis of modular data from quantum double subfactors, particularly those of
the double of cyclic groups, the symmetric group on 3 letters and the double of
the subfactors with principal graph the extended Dynkin diagram D_5^(1). In
particular for the double of S_3, 14 of the 48 modular modular invariants are
nimless, and only 28 of the remaining 34 nimble invariants can be realised by
subfactors
Zero-Range Processes with Multiple Condensates: Statics and Dynamics
The steady-state distributions and dynamical behaviour of Zero Range
Processes with hopping rates which are non-monotonic functions of the site
occupation are studied. We consider two classes of non-monotonic hopping rates.
The first results in a condensed phase containing a large (but subextensive)
number of mesocondensates each containing a subextensive number of particles.
The second results in a condensed phase containing a finite number of extensive
condensates. We study the scaling behaviour of the peak in the distribution
function corresponding to the condensates in both cases. In studying the
dynamics of the condensate we identify two timescales: one for creation, the
other for evaporation of condensates at a given site. The scaling behaviour of
these timescales is studied within the Arrhenius law approach and by numerical
simulations.Comment: 25 pages, 18 figure
The Age-Specific Force of Natural Selection and Walls of Death
W. D. Hamilton's celebrated formula for the age-specific force of natural
selection furnishes predictions for senescent mortality due to mutation
accumulation, at the price of reliance on a linear approximation. Applying to
Hamilton's setting the full non-linear demographic model for mutation
accumulation of Evans et al. (2007), we find surprising differences. Non-linear
interactions cause the collapse of Hamilton-style predictions in the most
commonly studied case, refine predictions in other cases, and allow Walls of
Death at ages before the end of reproduction. Haldane's Principle for genetic
load has an exact but unfamiliar generalization.Comment: 27 page
Studying a relativistic field theory at finite chemical potential with the density matrix renormalization group
The density matrix renormalization group is applied to a relativistic complex
scalar field at finite chemical potential. The two-point function and various
bulk quantities are studied. It is seen that bulk quantities do not change with
the chemical potential until it is larger than the minimum excitation energy.
The technical limitations of the density matrix renormalization group for
treating bosons in relativistic field theories are discussed. Applications to
other relativistic models and to nontopological solitons are also suggested.Comment: 9 pages, 5 figures; v2: title changed; references added, conclusions
expanded, to be published in PR
An Investigation into the Effects of Lateral Aerodynamic Asymmetries, Lateral Weight Asymmetries, and Differential Stabilator Bias on the F-15 Directional Flight Characteristics at High Angles of Attack
The F-15 is a stable aircraft throughout most of its flight envelope. However, it still exhibits an uncommanded yawing and rolling tendency at high angles-of-attack. Identified influencing factors of this uncommanded motion are lateral aerodynamic asymmetries, lateral weight asymmetries, and differential stabilator bias. Previous research into the effects of these influencing factors has been qualitative. This thesis quantifies the effects and then identifies a symmetric F-15 configuration. The quantifying metric presented is net yaw acceleration. This thesis used both computer simulation and experimental flight test to quantify these effects. A discussion of each influencing factors effects on the F-15B high AOA net yaw acceleration is presented. Aerodynamic asymmetries of the baseline F-15B are shown to cause a right yaw. Lateral weight asymmetries are shown to cause yaw acceleration away from the weight asymmetry. And, small changes in differential stabilator bias are shown to have little influence on net yaw acceleration. Considering these discussions, the baseline F-15B is identified as the symmetric F-15B. Finally, this thesis identifies two possible causes for F-15 departures, transient net yaw acceleration and combined sense of yaw and roll rate. The understandings of these possible causes on F-15 departures are just beginning to be evaluated
Recommended from our members
Technology in Nonformal Education: A Critical Appraisal
Issue Papers are a series of monographs written by and for theorists and practitioners in the field of nonformal education. Ranging broadly over ethical, theoretical and practical issues in nonformal education, the series is designed to reflect the current conceptual state of the art, its pitfalls and potentialities, and to focus attention on fundamental philosophic and behavioral tenets of the field
- …