3,108 research outputs found
Problem-solving Research for Management: A Perspective
We convened a symposium titled "Problem-solving Research for Management: Shared
Responsibilities" at the 123rd annual meeting of the American Fisheries Society in Portland,
Oregon. Our symposium sought to encourage researchers and managers to work together
more effectively by reviewing successful research projects that have incorporated problemsolving
approaches. In this first paper, we carefully define and distinguish between management
and research by exploring the goals and tools of each discipline. In our view, problemsolving
for management, as an iterative approach of which research is a major component,
serves as a template for improving the relationship between managers and researchers as well
as contributing to the solution of management problems. To improve the less-than-stellar
record of interaction between these two groups, not only must problem-solving approaches be
incorporated into the effort, but managers and researchers also must come to recognize, appreciate,
and understand the differences in tools and goals of their respective trades. Unfortunately,
we think neither group appreciates that successful management relies on rigorous, quantitative
research that must be held accountable for providing management solutions. Managers
and researchers clearly share the burden for the current state of fisheries science
Extragalactic Point Source Search in Five-year WMAP 41, 61 and 94 GHz Maps
We present the results of an extragalactic point source search using the
five-year WMAP 41, 61 and 94 GHz (Q-, V- and W-band) temperature maps. This
work is an extension of our point source search in the WMAP maps applying a
CMB-free technique. An internal linear combination (ILC) map has been formed
from the three-band maps, with the weights chosen to remove the CMB anisotropy
signal as well as to favor a selection of flat-spectrum sources. We find 381
sources at the > 5 sigma level outside the WMAP point source detection mask in
the ILC map, among which 89 are "new" (i.e., not present in the WMAP catalog).
Source fluxes have been calculated and corrected for the Eddington bias. We
have solidly identified 367 (96.3%) of our sources. The 1 sigma positional
uncertainty is estimated to be 2'. The 14 unidentified sources could be either
extended radio structure or obscured by Galactic emission. We have also applied
the same detection process on simulated maps and found 364+/-21 detections on
average. The recovered source distribution N(>S) agrees well with the
simulation input, which proves the reliability of this method.Comment: 28 pages, 9 figures, 2 tables, accepted by Ap
The Expected Rate of Gamma-Ray Burst Afterglows In Supernova Searches
We predict the rate at which Gamma-Ray Burst (GRB) afterglows should be
detected in supernova searches as a function of limiting flux. Although GRB
afterglows are rarer than supernovae, they are detectable at greater distances
because of their higher intrinsic luminosity. Assuming that GRBs trace the
cosmic star formation history and that every GRB gives rise to a bright
afterglow, we find that the average detection rate of supernovae and afterglows
should be comparable at limiting magnitudes brighter than K=18. The actual rate
of afterglows is expected to be somewhat lower since only a fraction of all
gamma-ray selected GRBs were observed to have associated afterglows. However,
the rate could also be higher if the initial gamma-ray emission from GRB
sources is more beamed than their late afterglow emission. Hence, current and
future supernova searches can place strong constraints on the afterglow
appearance fraction and the initial beaming angle of GRB sources.Comment: 13 pages, submitted to ApJ
Management Issues and Their Relative Priority within State Fisheries Agencies
For researchers and managers to work together for greatest mutual benefit, researchers must understand
what issues fisheries managers consider most important. To assess management priorities, we conducted a
mail survey asking U.S. state fisheries agencies to identify the priority, based on personnel time, they place
on 12 fisheries management issues. Based on an 88% response rate, we determined relative emphases across (1) management issues, (2) geographic regions, and (3) freshwater or marine orientations. Issues
directly linked to sport and commercial fishers, i.e., stocking, harvest regulations, fishing pressure, and
exploring recruitment, were of paramount importance in all agency time budgets. The issue that included
conflict, policy, and human dimensions concerns also was identified as "high priority." Six other issueshabitat
restoration, hydropower licensing, instream flow, contaminants, introduced species, and nongame
species-were of "moderate priority" nationwide. Approximately 50% of the issues varied in emphases
across geographic region, and five issues were differentially emphasized in agencies with freshwater and
marine responsibilities. To solve persistent problems that plague fisheries management, agencies must
clearly identify high-priority management concerns and communicate their specific problem-solving
needs to researchers. Results of this survey should provide a first step in identifying these management
priorities and research needs
Submillimeter wavelength survey of the galactic plane from l = -5 deg to l = +62 deg: Structure and energetics of the inner disk
Results from a large scale survey of the first quadrant of the Milky Way galactic plane at wavelengths of 150, 250, and 300 microns with a 10x10 arcmin beam are presented. The emission detected in the survey arises from compact sources, most of which are identified with known peaks of 5 GHz and/or CO emission, and from an underlying diffuse background with a typical angular width of approximately 0.9 deg (FWHM) which accounts for most of the emission. A total of 80 prominent discrete sources were identified and characterized, of which about half were not previously reported at far infrared wavelengths. The total infrared luminosity within the solar circle is approximately 1 to 2x10 to the 10th power L sub 0, and is probably emitted by dust that resides in molecular clouds
A new kind of Lax-Oleinik type operator with parameters for time-periodic positive definite Lagrangian systems
In this paper we introduce a new kind of Lax-Oleinik type operator with
parameters associated with positive definite Lagrangian systems for both the
time-periodic case and the time-independent case. On one hand, the new family
of Lax-Oleinik type operators with an arbitrary as
initial condition converges to a backward weak KAM solution in the
time-periodic case, while it was shown by Fathi and Mather that there is no
such convergence of the Lax-Oleinik semigroup. On the other hand, the new
family of Lax-Oleinik type operators with an arbitrary
as initial condition converges to a backward weak KAM solution faster than the
Lax-Oleinik semigroup in the time-independent case.Comment: We give a new definition of Lax-Oleinik type operator; add some
reference
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