34,935 research outputs found
Ocean shrimp report 1977 season
Statewide Pacific ocean shrimp, Pandalus jordani, landings
totaled 15,639,585 lb, more than triple the 1975 record catch of 4,992,233 lb. Record landings were recorded in Area A (Eureka-Crescent City), Area B-2 (Bodega Ray) with catches
totaling 13,025,844 and 2,028,607 lb, respectively. Area B-1
(Fort Bragg) landings totaled 585,133 lb and no landings were reported from Area C (Avila-Morro Bay). In Area A the average catch per hour for the season for single-rig vessels was 1,241 lb and 2,228 lb for double-rig vessels. Area B-2 average catch per hour by the single-rig vessels was 2,536 lb. Two-year-old (1975 year class) shrimp dominated the catches in all areas. The outlook for the 1978 season in all areas is questionable because of the relatively weak showing of the incoming 1977 year class but it might make a significant contribution if abundant and of a marketable slze. (19pp.
Ocean shrimp report 1978 season
Statewide Pacific ocean shrimp, Pandalus jordani, landings
totaled 13,163,243 lb, down about 2.5 million lb from the 1977 record catch of 15,639,584 lb. However, the 1978 landings were still the second highest on record. Area A (Eureka-Crescent City) landings were the second
highest in history with landings of 11,101,895 lb. Landings of 2,061,348 lb in Area B-1 (Fort Bragg) broke all existing records for the bed. The previous record was 799,722 lb landed in 1961. No landings were reported for Areas B-2 (Bodega Bay) and C (Avila-Morro Bay). In Area A the average catch per hour for the season for single-rig vessels was 581 lb and 862 lb for double-rig vessels. Area B-1 average
catch per hour was 819 lb and 1,069 lb per hour for single-rig and double-rig vessels, respectively. Two-year-old (1976 year class) shrimp dominated the catches during the first three months in Area A and throughout the season in Area B-1. One-year-old (1977 year class)
shrimp dominated the catches in Area A from July to the end of the season. Catches during the first part of October in Area A fell below the established criteria for keeping the season open. This necessitated closing the season two weeks early. (16pp.
Evolution in banking competition
An abstract for this article is not available.Banks and banking ; Competition
Ocean shrimp report 1979 season
Statewide Pacific ocean shrimp, Pandalus jordani, landings
totaled 2,237.7 mt (4,922,857 lb), down 3,745 mt
(8,240,386 lb) from the 1978 catch of 5,983.3 mt
(13,163,243 lb). The 1979 landings are the lowest
since 1976 when 1,545.5 mt (3,400,191 lb) were landed. Area A (Eureka-Crescent City)landings dropped to 1,842.5 mt (4,053,605 lb) from 5,046.3 mt (11,101,895 lb) landed during the previous season. No landings were made in Area B-1 (Fort Bragg). Only 2.0 mt (4,385 lb) were reported caught in Area B-2 (Bodega Bay). Record landings of 393.1 mt
(864,867 lb) were made in Area C (Morro Bay-Avila), surpassing the previous record of 90.4 mt (199,000 lb) landed in 1953. In Area A a record 71 vessels, 34 double-rigged and 37 single-rigged, shrimped during the
season. Average catch per hour was a low .15 mt (338 lb) and .22 mt (490 1b) for single-rig and double-rig vessels, respectively. In Area C average catch per hour was .23 mt (508 lb) and .42 mt (924 lb) for single-rig and double-rig
vessels, respectively. Area A shrimp catches were dominated by 1-year-old shrimp throughout most of the season. The
age composition in Area C shifted predominately from 2-year-old shrimp in May and June to predominately 1-year-old shrimp in July, August, October, and November. Area A was closed for one month from July 15 to
August 15 because closure criteria of less than .16 mt
(350 lb) per hour for two consecutive weeks was met and year class composition exceeded 70% of 1-year-old shrimp. The season was closed October 14 when the catch per hour criterion was exceeded again. (18pp.
A stacking method to study the gamma-ray emission of source samples based on the co-adding of Fermi LAT count maps
We present a stacking method that makes use of co-added maps of gamma-ray
counts produced from data taken with the Fermi Large Area Telescope. Sources
with low integrated gamma-ray fluxes that are not detected individually may
become detectable when their corresponding count maps are added. The combined
data set is analyzed with a maximum likelihood method taking into account the
contribution from point-like and diffuse background sources. For both simulated
and real data, detection significance and integrated gamma-ray flux are
investigated for different numbers of stacked sources using the public Fermi
Science Tools for analysis and data preparation. The co-adding is done such
that potential source signals add constructively, in contrast to the signals
from background sources, which allows the stacked data to be described with
simply structured models. We show, for different scenarios, that the stacking
method can be used to increase the cumulative significance of a sample of
sources and to characterize the corresponding gamma-ray emission. The method
can, for instance, help to search for gamma-ray emission from galaxy clusters.Comment: accepted for publication in Astronomy & Astrophysics, 10 pages, 12
figure
Error bounds on block Gauss Seidel solutions of coupled\ud multiphysics problems
Mathematical models in many fields often consist of coupled sub–models, each of which describe a different physical process. For many applications, the quantity of interest from these models may be written as a linear functional of the solution to the governing equations. Mature numerical solution techniques for the individual sub–models often exist. Rather than derive a numerical solution technique for the full coupled model, it is therefore natural to investigate whether these techniques may be used by coupling in a block Gauss–Seidel fashion. In this study, we derive two a posteriori bounds for such linear functionals. These bounds may be used on each Gauss–Seidel iteration to estimate the error in the linear functional computed using the single physics solvers, without actually solving the full, coupled problem. We demonstrate the use of the bound first by using a model problem from linear algebra, and then a linear ordinary differential equation example. We then investigate the effectiveness of the bound using a non–linear coupled fluid–temperature problem. One of the bounds derived is very sharp for most linear functionals considered, allowing us to predict very accurately when to terminate our block Gauss–Seidel iteration.\ud
\ud
Copyright c 2000 John Wiley & Sons, Ltd
Market Structure in the Residential Real Estate Brokerage Market
This study provides empirical evidence regarding brokerage firm concentration in a local market multiple listing service setting over the year 1992-1995. To evaluate the level of brokerage firm concentration in this market, Gini Coefficients, Herfindahl-Hirschman Indices and Concentration Ratios for each year of the study period are calculated. Our results indicate that for firms responsible for listing properties, firm concentration has not varied substantially over the four-year study period. However, for those firms that were responsible for actually selling properties, firm concentration has decreased over the study period. This finding tends to indicate that the MLS now provides greater exposure to a wide variety of sales firms, therefore leading to a higher level of competition with a lower level of concentration for selling firms in this local market.
Efficient algorithms for tensor scaling, quantum marginals and moment polytopes
We present a polynomial time algorithm to approximately scale tensors of any
format to arbitrary prescribed marginals (whenever possible). This unifies and
generalizes a sequence of past works on matrix, operator and tensor scaling.
Our algorithm provides an efficient weak membership oracle for the associated
moment polytopes, an important family of implicitly-defined convex polytopes
with exponentially many facets and a wide range of applications. These include
the entanglement polytopes from quantum information theory (in particular, we
obtain an efficient solution to the notorious one-body quantum marginal
problem) and the Kronecker polytopes from representation theory (which capture
the asymptotic support of Kronecker coefficients). Our algorithm can be applied
to succinct descriptions of the input tensor whenever the marginals can be
efficiently computed, as in the important case of matrix product states or
tensor-train decompositions, widely used in computational physics and numerical
mathematics.
We strengthen and generalize the alternating minimization approach of
previous papers by introducing the theory of highest weight vectors from
representation theory into the numerical optimization framework. We show that
highest weight vectors are natural potential functions for scaling algorithms
and prove new bounds on their evaluations to obtain polynomial-time
convergence. Our techniques are general and we believe that they will be
instrumental to obtain efficient algorithms for moment polytopes beyond the
ones consider here, and more broadly, for other optimization problems
possessing natural symmetries
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Length-length and weight-length relationships of seven deep-water fishes in the Gulf of Mexico
Regression coefficients for equations of the form Y = a + bX were estimated for total length (TL) and whole weight (W) as a function of standard length (SL) and fork length (FL) and vice versa for seven deep-water fishes. All lengths were measured in millimeters and all weights in grams. There was a significant correlation between weight and length and the types of length measurements for all species. However, the amount of variation explained by each regression varied among species. Weight-length regressions were less precise than length-length regression, as they generally are, because weights of small fish measured at sea are more inaccurate than those of large fish.Marine Scienc
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