2,313 research outputs found
An LP-based inconsistency monitoring of pairwise comparison matrices
A distance-based inconsistency indicator, defined by the third author for the consistency-driven pairwise comparisons method, is extended to the incomplete case. The corresponding optimization problem is transformed into an equivalent linear programming problem. The results can be applied in the process of filling in the matrix as the decision maker gets automatic feedback. As soon as a serious error occurs among the matrix elements, even due to a misprint, a significant increase in the inconsistency index is reported. The high inconsistency may be alarmed not only at the end of the process of filling in the matrix but also during the completion process. Numerical examples are also provided
Forest Charges and Trusts: Shared Benefits with Clear Responsibilities
This paper examines the Community-Based Forest Management Program (CBFM) and Industrial Forest Management Agreements (IFMA) within the context of efficient forest management. Investigation on ways of accomplishing the objectives of the agency, community and commercial forestry in decreased costs is conducted. Results show a need for DENR’s redirection of financial and human resources to focus on critical environmental tasks. Focus on higher-value timber opportunities can increase the potential for sustainable management and increase in the government revenue collection.forestry sector, rent and fee
Forest Charges and Trusts: Shared Benefits with Clear Responsibilities
This paper examines the Community-Based Forest Management Program (CBFM) and Industrial Forest Management Agreements (IFMA) within the context of efficient forest management. Investigation on ways of accomplishing the objectives of the agency, community and commercial forestry in decreased costs is conducted. Results show a need for DENR’s redirection of financial and human resources to focus on critical environmental tasks. Focus on higher-value timber opportunities can increase the potential for sustainable management and increase in the government revenue collection.forestry sector, rent and fee
Absorption Efficiencies of Forsterite. I: DDA Explorations in Grain Shape and Size
We compute the absorption efficiency (Qabs) of forsterite using the discrete
dipole approximation (DDA) in order to identify and describe what
characteristics of crystal grain shape and size are important to the shape,
peak location, and relative strength of spectral features in the 8-40 {\mu}m
wavelength range. Using the DDSCAT code, we compute Qabs for non-spherical
polyhedral grain shapes with a_eff = 0.1 {\mu}m. The shape characteristics
identified are: 1) elongation/reduction along one of three crystallographic
axes; 2) asymmetry, such that all three crystallographic axes are of different
lengths; and 3) the presence of crystalline faces that are not parallel to a
specific crystallographic axis, e.g., non-rectangular prisms and (di)pyramids.
Elongation/reduction dominates the locations and shapes of spectral features
near 10, 11, 16, 23.5, 27, and 33.5 {\mu}m, while asymmetry and tips are
secondary shape effects. Increasing grain sizes (0.1-1.0 {\mu}m) shifts the 10,
11 {\mu}m features systematically towards longer wavelengths and relative to
the 11 {\mu}m feature increases the strengths and slightly broadens the longer
wavelength features. Seven spectral shape classes are established for
crystallographic a-, b-, and c-axes and include columnar and platelet shapes
plus non-elongated or equant grain shapes. The spectral shape classes and the
effects of grain size have practical application in identifying or excluding
columnar, platelet or equant forsterite grain shapes in astrophysical environs.
Identification of the shape characteristics of forsterite from 8-40 {\mu}m
spectra provides a potential means to probe the temperatures at which
forsterite formed.Comment: 55 pages, 15 figure
The impact of sea-level rise on tidal characteristics around Australia
An established tidal model, validated for present-day conditions, is used to
investigate the effect of large levels of sea-level rise (SLR) on tidal
characteristics around Australasia. SLR is implemented through a uniform
depth increase across the model domain, with a comparison between the
implementation of coastal defences or allowing low-lying land to flood. The
complex spatial response of the semi-diurnal M2 constituent does not
appear to be linear with the imposed SLR. The most predominant features of
this response are the generation of new amphidromic systems within the Gulf
of Carpentaria and large-amplitude changes in the Arafura Sea, to the north
of Australia, and within embayments along Australia's north-west coast.
Dissipation from M2 notably decreases along north-west Australia but is
enhanced around New Zealand and the island chains to the north. The diurnal
constituent, K1, is found to decrease in amplitude in the Gulf of
Carpentaria when flooding is allowed. Coastal flooding has a profound impact
on the response of tidal amplitudes to SLR by creating local regions of
increased tidal dissipation and altering the coastal topography. Our results
also highlight the necessity for regional models to use correct open boundary
conditions reflecting the global tidal changes in response to SLR.</p
Spitzer Observations of Comet 67P/Churyumov-Gerasimenko at 5.5-4.3 AU From the Sun
We report Spitzer Space Telescope observations of comet
67P/Churyumov-Gerasimenko at 5.5 and 4.3 AU from the Sun, post-aphelion. Comet
67P is the primary target of the European Space Agency's Rosetta mission. The
Rosetta spacecraft will rendezvous with the nucleus at heliocentric distances
similar to our observations. Rotationally resolved observations at 8 and 24
microns (at a heliocentric distance, rh, of 4.8 AU) that sample the size and
color-temperature of the nucleus are combined with aphelion R-band light curves
observed at the Very Large Telescope (VLT) and yield a mean effective radius of
2.04 +/- 0.11 km, and an R-band geometric albedo of 0.054 +/- 0.006. The
amplitudes of the R-band and mid-infrared light curves agree, which suggests
that the variability is dominated by the shape of the nucleus. We also detect
the dust trail of the comet at 4.8 and 5.5 AU, constrain the grain sizes to be
less than or similar to 6 mm, and estimate the impact hazard to Rosetta. We
find no evidence for recently ejected dust in our images. If the activity of
67P is consistent from orbit to orbit, then we may expect the Rosetta
spacecraft will return images of an inactive or weakly active nucleus as it
rendezvous with the comet at rh = 4 AU in 2014.Comment: 19 pages, 2 tables, 10 figures. Accepted for publication in the
Astronomical Journa
Radius Dependent Luminosity Evolution of Blue Galaxies in GOODS-N
We examine the radius-luminosity (R-L) relation for blue galaxies in the Team
Keck Redshift Survey (TKRS) of GOODS-N. We compare with a volume-limited, Sloan
Digital Sky Survey sample and find that the R-L relation has evolved to lower
surface brightness since z=1. Based on the detection limits of GOODS this can
not be explained by incompleteness in low surface-brightness galaxies. Number
density arguments rule out a pure radius evolution. It can be explained by a
radius dependent decline in B-band luminosity with time. Assuming a linear
shift in M_B with z, we use a maximum likelihood method to quantify the
evolution. Under these assumptions, large (R_{1/2} > 5 kpc), and intermediate
sized (3 < R_{1/2} < 5 kpc) galaxies, have experienced Delta M_B =1.53
(-0.10,+0.13) and 1.65 (-0.18, +0.08) magnitudes of dimming since z=1. A simple
exponential decline in star formation with an e-folding time of 3 Gyr can
result in this amount of dimming. Meanwhile, small galaxies, or some subset
thereof, have experienced more evolution, 2.55 (+/- 0.38) magnitudes. This
factor of ten decline in luminosity can be explained by sub-samples of
starbursting dwarf systems that fade rapidly, coupled with a decline in burst
strength or frequency. Samples of bursting, luminous, blue, compact galaxies at
intermediate redshifts have been identified by various previous studies. If
there has been some growth in galaxy size with time, these measurements are
upper limits on luminosity fading.Comment: 34 Total pages, 15 Written pages, 19 pages of Data Table, 13 Figures,
accepted for publication in Ap
Mid-Infrared Spectrophotometric Observations of Fragments B and C of Comet 73P/Schwassmann-Wachmann 3
We present mid-infrared spectra and images from the GEMINI-N (+Michelle)
observations of fragments SW3-[B] and SW3-[C] of the ecliptic (Jupiter Family)
comet 73P/Schwassmann-Wachmann 3 pre-perihelion. We observed fragment B soon
after an outburst event (between 2006 April 16 - 26 UT) and detected
crystalline silicates. The mineralogy of both fragments was dominated by
amorphous carbon and amorphous pyroxene. The grain size distribution (assuming
a Hanner modified power-law) for fragment SW3-[B] has a peak grain radius of
a_p ~ 0.5 micron, and for fragment SW3-[C], a_p ~ 0.3 micron; both values
larger than the peak grain radius of the size distribution for the dust ejected
from ecliptic comet 9P/Tempel 1 during the Deep Impact event (a_p = 0.2 micron.
The silicate-to-carbon ratio and the silicate crystalline mass fraction for the
submicron to micron-size portion of the grain size distribution on the nucleus
of fragment SW3-[B] was 1.341 +0.250 -0.253 and 0.335 +0.089 -0.112,
respectively, while on the nucleus of fragment SW3-[C] was 0.671 +0.076 -0.076
and 0.257 +0.039 -0.043, respectively. The similarity in mineralogy and grain
properties between the two fragments implies that 73P/Schwassmann-Wachmann 3 is
homogeneous in composition. The slight differences in grain size distribution
and silicate-to-carbon ratio between the two fragments likely arises because
SW3-[B] was actively fragmenting throughout its passage while the activity in
SW3-[C] was primarily driven by jets. The lack of diverse mineralogy in the
fragments SW3-[B] and SW3-[C] of 73P/Schwassmann-Wachmann 3 along with the
relatively larger peak in the coma grain size distribution suggests the parent
body of this comet may have formed in a region of the solar nebula with
different environmental properties than the natal sites where comet C/1995 O1
(Hale-Bopp) and 9P/Tempel 1 nuclei aggregated.Comment: 31 pages, 5 figure, accepted for publication in A
Further evidence for linearly-dispersive Cooper pairs
A recent Bose-Einstein condensation (BEC) model of several cuprate
superconductors is based on bosonic Cooper pairs (CPs) moving in 3D with a
quadratic energy-momentum (dispersion) relation. The 3D BEC condensate-fraction
vs. temperature (T/Tc, where Tc is the BEC transition temperature) formula
poorly fits penetration-depth data for two cuprates in the range (1/2, 1]. We
show how these fits are dramatically improved assuming cuprates to be quasi-2D,
and how equally good fits obtain for conventional 3D and quasi-1D nanotube
superconducting data, provided the correct CP dispersion is assumed in BEC at
their assumed corresponding dimensionalities. This is offered as additional
concrete empirical evidence for linearly-dispersive pairs in another recent BEC
scenario of superconductors within which a BCS condensate turns out to be a
very special case.Comment: 9 pages, 1 figur
- …