5,557 research outputs found
The Shreveport Caddo, 1835-1838
Period records, such as the reports of Many, Bonnell and Riley, clearly make reference to at least four Caddo villages located between the Red River and the United States-Mexico/Texas boundary in the mid-1830s. In the early 1990s, one of these sites, Timber Hill, was located just to the west of Jim\u27s Bayou in Marion County. In this article I will discuss the location and demise of at least four and possible five additional 1830s-era villages located south of Caddo Lake. In the interest of preserving the sites mentioned, the specific locations of the villages discussed in this article are approximate
Performance of the IUE Spacecraft Batteries After 70 Months
The battery performance of the IUE spacecraft launched in 1977 is updated. Changes made in the battery operational procedures are detailed. The aging effects after several eclipse seasons and the effects of 8 C temperature was anticipated. The batteries met their design goals and should meet the 10 year goal
A five-year study of the striped bass fishery of Maryland, based on analyses of the scales
The striped bass, or rock as the species is called in the Chesapeake area, ranks high in value and volume among the commercially important fish taken in Maryland waters and, in addition, is highly prized as a game fish by sportsmen. Interest in the marked fluctuations characteristic of the species stimulated the investigation begun in October, 1941
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Human Trafficking in the Emergency Department: Improving Our Response to a Vulnerable Population
Human trafficking is a human rights violation affecting millions worldwide. Victims may go unrecognized during their emergency department (ED) visit, and may lose the opportunity to address their complex needs. Using a published toolkit based on existing guidelines and recommendations from experts, and models from other centers, we describe the implementation of an ED response protocol. In following the recommendations of the toolkit, we began with attempts to fully understand the local human trafficking problem and then networked with those working in anti-trafficking efforts. Collaboration with other specialties is highlighted as a key part of this process. Building upon the knowledge gained from these steps, we were able to develop a concise protocol to guide members of our department in more effectively caring for known or suspected victims of human trafficking. The first section of the protocol addresses ways in which providers can identify at-risk patients through both screening questions and general observations. Interviewing techniques are outlined with an emphasis on patient-centered and trauma-informed care. Additionally, the protocol discusses physician responsibility in documenting encounters and legal reporting, which may vary depending on location. We stress the importance of meeting the needs of the patient while prioritizing the safety of all involved. Additionally, the protocol provides a list of resources for the patient beyond medical care such as emergency housing, legal assistance, and food pantries. The overall purpose of this protocol is to provide coordinated response so that all providers may be consistent in caring for this vulnerable population
Preliminary Observations on spawning potential in the striped bass (Roccus saxatilis Walbaum)
This study was initiated during the summer of 1940 with the following objectives: (1) To determine at what age sexual maturity begins in striped bass of the Chesapeake Bay. (2) To determine whether the potential of reproduction declines with increasing age in Chesapeake Bay fish. (3) To determine whether striped bass in northern waters have a spawning cycle similar to that found in the Chesapeake Bay fish
Bootstrap Approximation to Prediction MSE for State-Space Models with Estimated Parameters
We propose a simple but general bootstrap method for estimating the Prediction Mean Square Error (PMSE) of the state vector predictors when the unknown model parameters are estimated from the observed series. As is well known, substituting the model parameters by the sample estimates in the theoretical PMSE expression that assumes known parameter values results in under-estimation of the true PMSE. Methods proposed in the literature to deal with this problem in state-space modelling are inadequate and may not even be operational when fitting complex models, or when some of the parameters are close to their boundary values. The proposed method consists of generating a large number of series from the model fitted to the original observations, re-estimating the model parameters using the same method as used for the observed series and then estimating separately the component of PMSE resulting from filter uncertainty and the component resulting from parameter uncertainty. Application of the method to a model fitted to sample estimates of employment ratios in the U.S.A. that contains eighteen unknown parameters estimated by a three-step procedure yields accurate results. The procedure is applicable to mixed linear models that can be cast into state-space form. (Updated 6th October 2004
State-space modeling with correlated measurements with application to small area estimation under benchmark constraints
The problem of Small Area Estimation is how to produce reliable estimates of area (domain) characteristics, when the sizes within the areas are too small to warrant the use of traditional direct survey estimates. This problem is commonly tackled by borrowing information from either neighboring areas and/or from previous surveys, using appropriate time series/cross-sectional models. In order to protect against possible model breakdowns and for other reasons, it is often required to benchmark the model dependent estimates to the corresponding direct survey estimates in larger areas, for which the survey estimates are sufficiently accurate. The benchmarking process defines another way of borrowing information across the areas.This article shows how benchmarking can be implemented with the state-space models used by the Bureau of Labor Statistics in the U.S. for the production of the monthly employment and unemployment estimates at the state level. The computation of valid estimators for the variances of the benchmarked estimators requires joint modeling of the direct estimators in several states, which in turn requires the development of a filtering algorithm for state-space models with correlated measurement errors. No such algorithm has been developed so far. The application of the proposed procedure is illustrated using real unemployment series
Comparison of Two Algebraic Methods for Curve/curve Intersection
Most geometric modeling systems use either polynomial or rational functions to represent geometry. In such systems most computational problems can be formulated as systems of polynomials in one or more variables. Classical elimination theory can be used to solve such systems. Here Cayley's method of elimination is summarized and it is shown how it can best be used to solve the curve/curve intersection problem. Cayley's method was found to be a more straightforward approach. Furthermore, it is computationally simpler, since the elements of the Cayley matrix are one variable instead of two variable polynomials. Researchers implemented and tested both methods and found Cayley's to be more efficient. Six pairs of curves, representing mixtures of lines, circles, and cubic arcs were used. Several examples had multiple intersection points. For all six cases Cayley's required less CPU time than the other method. The average time ratio of method 1 to method 2 was 3.13:1, the least difference was 2.33:1, and the most dramatic was 6.25:1. Both of the above methods can be extended to solve the surface/surface intersection problem
Update of the IUE battery in-flight performance
The in-flight performance data of two 17-cell, 6-ampere-hour nickel cadmium spacecraft batteries are presented covering 22 months of operation. Fluctuations in the battery voltage and the battery temperature are presented for spacecraft movement throughout a beta range of 0 to 130 deg. The battery discharge voltages during the peak eclipse seasons, daily seasons, and daily eclipse periods are noted. Finally, the spacecraft data are compared to data from a 6-ampere-hour test pack and test flight data
The LDEF heat pipe experiment power systems
A heatpipe experiment for a long duration exposure facility is described. The design and configuration of the power system of the spacecraft is reported with emphasis placed on its solar array panels, 12-ampere hour 18-cell nickel battery, and its electronic controller
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