916 research outputs found
REGIONAL ECONOMIC IMPACTS OF REDUCTIONS IN FISHERIES PRODUCTION: A SUPPLY-DRIVEN APPROACH
Much debate and subsequent confusion have recently been generated regarding the economic importance of the longline fisheries for tuna and swordfish in Hawaii. Depending on the methodology employed, the measures of the economic importance of these fisheries to Hawaii can vary significantly. This paper attempts to provide an assessment of the alternative measures and their implications for fishery policy. In assessing the economic impact of the reduction in longline activities due to season and area closures as mandated by a recent court order, we suggest that the supply-driven approach is more appropriate. An empirical application using the supply-driven approach is used to estimate the economy-wide impacts of a 100% reduction in Hawaii-based longline activities. In addition, a set of supply-driven multipliers is derived for the other sectors of Hawaii's economy to allow comparison with the fishery sectors.Resource /Energy Economics and Policy,
Combining domain knowledge and statistical models in time series analysis
This paper describes a new approach to time series modeling that combines
subject-matter knowledge of the system dynamics with statistical techniques in
time series analysis and regression. Applications to American option pricing
and the Canadian lynx data are given to illustrate this approach.Comment: Published at http://dx.doi.org/10.1214/074921706000001049 in the IMS
Lecture Notes Monograph Series
(http://www.imstat.org/publications/lecnotes.htm) by the Institute of
Mathematical Statistics (http://www.imstat.org
Gradient-based quantitative image reconstruction in ultrasound-modulated optical tomography: first harmonic measurement type in a linearised diffusion formulation
Ultrasound-modulated optical tomography is an emerging biomedical imaging
modality which uses the spatially localised acoustically-driven modulation of
coherent light as a probe of the structure and optical properties of biological
tissues. In this work we begin by providing an overview of forward modelling
methods, before deriving a linearised diffusion-style model which calculates
the first-harmonic modulated flux measured on the boundary of a given domain.
We derive and examine the correlation measurement density functions of the
model which describe the sensitivity of the modality to perturbations in the
optical parameters of interest. Finally, we employ said functions in the
development of an adjoint-assisted gradient based image reconstruction method,
which ameliorates the computational burden and memory requirements of a
traditional Newton-based optimisation approach. We validate our work by
performing reconstructions of optical absorption and scattering in two- and
three-dimensions using simulated measurements with 1% proportional Gaussian
noise, and demonstrate the successful recovery of the parameters to within
+/-5% of their true values when the resolution of the ultrasound raster probing
the domain is sufficient to delineate perturbing inclusions.Comment: 12 pages, 6 figure
Developing a flexible framework for spatiotemporal population modeling
This article proposes a general framework for modeling population distributions in space and time. This is particularly pertinent to a growing range of applications that require spatiotemporal specificity; for example, to inform planning of emergency response to hazards. Following a review of attempts to construct time-specific representations of population, we identify the importance of assembling an underlying data model at the highest resolution in each of the spatial, temporal, and attribute domains. This model can then be interrogated at any required intersection of these domains. We argue that such an approach is necessary to moderate the effects of what we term the modifiable spatiotemporal unit problem in which even detailed spatial data might be inadequate to support time-sensitive analyses. We present an initial implementation of the framework for a case study of Southampton, United Kingdom, using bespoke software (SurfaceBuilder247). We demonstrate the generation of spatial population distributions for multiple reference times using currently available data sources. The article concludes by setting out key research areas including the enhancement and validation of spatiotemporal population methods and model
Ranking algorithms for implicit feedback
This report presents novel algorithms to use eye movements as an implicit relevance feedback in order to improve the performance of the searches. The algorithms are evaluated on "Transport Rank Five" Dataset which were previously collected in Task 8.3. We demonstrated that simple linear combination or tensor product of eye movement and image features can improve the retrieval accuracy
Smart biosensors for multiplexed and fully integrated point-of-care diagnostics
Point-of-care diagnostics (PoC) and personalised medicine are highly valuable for the improvement of world health. Smartphone PoC platforms which precisely diagnose diseases and track their development through the detection of several bioanalytes represent one of the newest and most exciting advancements towards mass-screening applications. Here we focus on recent advances in both multiplexed and smartphone integrated PoC sensors
Directional optical switching and transistor functionality using optical parametric oscillation in a spinor polariton fluid
Over the past decade, spontaneously emerging patterns in the density of
polaritons in semiconductor microcavities were found to be a promising
candidate for all-optical switching. But recent approaches were mostly
restricted to scalar fields, did not benefit from the polariton's unique
spin-dependent properties, and utilized switching based on hexagon far-field
patterns with 60{\deg} beam switching (i.e. in the far field the beam
propagation direction is switched by 60{\deg}). Since hexagon far-field
patterns are challenging, we present here an approach for a linearly polarized
spinor field, that allows for a transistor-like (e.g., crucial for
cascadability) orthogonal beam switching, i.e. in the far field the beam is
switched by 90{\deg}. We show that switching specifications such as
amplification and speed can be adjusted using only optical means
07361 Abstracts Collection -- Programming Models for Ubiquitous Parallelism
From 02.09. to 07.09.2007, the Dagstuhl Seminar 07361 ``Programming Models for Ubiquitous Parallelism\u27\u27 was held
in the International Conference and Research Center (IBFI),
Schloss Dagstuhl.
During the seminar, several participants presented their current
research, and ongoing work and open problems were discussed. Abstracts of
the presentations given during the seminar as well as abstracts of
seminar results and ideas are put together in this paper. The first section
describes the seminar topics and goals in general.
Links to extended abstracts or full papers are provided, if available
A Case of Beare-Stevenson Syndrome with Unusual Manifestations
Case series Patient: - Final Diagnosis: Beare-Stevenson syndrome Symptoms: - Medication: - Clinical Procedure: Genetic analysis Specialty: Pediatrics and Neonatology Objective: Rare disease Background: Beare-Stevenson syndrome (BSS) is an extremely rare genetic disorder, with fewer than 25 cases reported worldwide. This autosomal dominant syndrome has been linked to two mutations in the fibroblast growth factor receptor 2 gene (FGFR2), Tyr375Cys and Ser372Cys, both causing amino acid changes. Case Report: BSS is characterized by a range of morphological features, some more classically associated than others, of which craniosynostosis has been almost uniformly present. Other common features include cutis gyrata, acanthosis nigricans, ear and eye defects, skin/mucosal tissue tags, prominent umbilical stump, and anogenital anomalies. This account reports what we believe to be the 25th case of BSS, and exhibits a constellation of the characteristic features similar to those previously described, including the presence of cutis gyrata, proptosis, a bifid scrotum, and hypospadias. However, craniosynostosis was not detected prenatally by ultrasound or at birth. Prenatal ultrasound may detect some dysmorphic features of BSS. Many of these features have also been associated with other genetic disorders with overlapping phenotypes. Our case presented with the unusual features of a natal tooth and absence of craniosynostosis at birth. At birth, a diagnosis of BSS was suspected based on clinical features despite the absence of craniosynostosis. This was later confirmed with the use of molecular analysis, revealing a Tyr375Cys mutation of exon 9 of the FGFR2 gene. Conclusions: We suggest that a normal antenatal ultrasound scan and the absence of craniosynostosis at birth should not preclude further workup for BSS if this possibility is clinically suspected
- …