Lunar tidal acceleration obtained from satellite-derived ocean tide parameters

One hundred sets of mean elements of GEOS-3 computed at 2-day intervals yielded observation equations for the M sub 2 ocean tide from the long periodic variations of the inclination and node of the orbit. The 2nd degree Love number was given the value k sub 2 = 0.30 and the solid tide phase angle was taken to be zero. Combining obtained equations with results for the satellite 1967-92A gives the M sub 2 ocean tide parameter values. Under the same assumption of zero solid tide phase lag, the lunar tidal acceleration was found mostly due to the C sub 22 term in the expansion of the M sub 2 tide with additional small contributions from the 0 sub 1 and N sub 2 tides. Using Lambeck's (1975) estimates for the latter, the obtained acceleration in lunar longitudal in excellent agreement with the most recent determinations from ancient and modern astronomical data

Effects of tropospheric and ionospheric refraction errors in the utilization of GEOS-C altimeter data

The effects of tropospheric and ionospheric refraction errors are analyzed for the GEOS-C altimeter project in terms of their resultant effects on C-band orbits and the altimeter measurement itself. Operational procedures using surface meteorological measurements at ground stations and monthly means for ocean surface conditions are assumed, with no corrections made for ionospheric effects. Effects on the orbit height due to tropospheric errors are approximately 15 cm for single pass short arcs (such as for calibration) and 10 cm for global orbits of one revolution. Orbit height errors due to neglect of the ionosphere have an amplitude of approximately 40 cm when the orbits are determined from C-band range data with predominantly daylight tracking. Altimeter measurement errors are approximately 10 cm due to residual tropospheric refraction correction errors. Ionospheric effects on the altimeter range measurement are also on the order of 10 cm during the GEOS-C launch and early operation period

GEODYN system description, volume 1

A computer program for the estimation of orbit and geodetic parameters is presented. The areas in which the program is operational are defined. The specific uses of the program are given as: (1) determination of definitive orbits, (2) tracking instrument calibration, (3) satellite operational predictions, and (4) geodetic parameter estimation. The relationship between the various elements in the solution of the orbit and geodetic parameter estimation problem is analyzed. The solution of the problems corresponds to the orbit generation mode in the first case and to the data reduction mode in the second case

Tracing Appalachian Musical History through Fiction: Representations of Appalachian Music in Selected Works by Mildred Haun and Lee Smith

This research seeks to compare and contrast fictional Appalachian writings by Lee Smith and Mildred Haun to contemporary historical sources in an attempt to trace the development of Appalachian music between the mid-nineteenth century and the late twentieth century. The thesis examines two novels by Lee Smith (The Devil’s Dream and Oral History) and the collection The Hawk’s Done Gone by Mildred Haun, which includes a short novel and several short stories. Contemporary primary sources and scholarly secondary sources were used to compare the fictional works’ depictions of Appalachian music to their historical counterparts. Also included within the thesis is a discussion of Smith and Haun’s personal and research backgrounds and their connections to Appalachian music. Overall, the study found Smith and Haun’s works accurate and based in historical fact, in part due to both writers’ use of historical research and interviews to inform their fiction

Dewey Meets Bluegrass: Progressive Educational Theory in the Establishment of Traditional Music Programs in Higher Education

The study focuses on connections between the Progressive era educational theories of John Dewey and present-day bluegrass and traditional music programs in higher education in order to explore a pedagogical basis for such programs. The research specifically examines Dewey’s beliefs in experiential learning, individualization, and vocational education and their current applications in traditional music education. The study included two major components: historical research into Dewey’s writings and primary and secondary sources regarding traditional music education in the United States, and interviews of faculty members in college and university bluegrass and traditional music programs. The thesis of this study is that experiential learning historically has been part of traditional music education and that it is an essential aspect of bluegrass and traditional music programs in higher education in the present day, leading to students taking part in meaningful learning experiences that contribute to their occupational goals

Investigation for improving Global Positioning System (GPS) orbits using a discrete sequential estimator and stochastic models of selected physical processes

GEODYNII is a conventional batch least-squares differential corrector computer program with deterministic models of the physical environment. Conventional algorithms were used to process differenced phase and pseudorange data to determine eight-day Global Positioning system (GPS) orbits with several meter accuracy. However, random physical processes drive the errors whose magnitudes prevent improving the GPS orbit accuracy. To improve the orbit accuracy, these random processes should be modeled stochastically. The conventional batch least-squares algorithm cannot accommodate stochastic models, only a stochastic estimation algorithm is suitable, such as a sequential filter/smoother. Also, GEODYNII cannot currently model the correlation among data values. Differenced pseudorange, and especially differenced phase, are precise data types that can be used to improve the GPS orbit precision. To overcome these limitations and improve the accuracy of GPS orbits computed using GEODYNII, we proposed to develop a sequential stochastic filter/smoother processor by using GEODYNII as a type of trajectory preprocessor. Our proposed processor is now completed. It contains a correlated double difference range processing capability, first order Gauss Markov models for the solar radiation pressure scale coefficient and y-bias acceleration, and a random walk model for the tropospheric refraction correction. The development approach was to interface the standard GEODYNII output files (measurement partials and variationals) with software modules containing the stochastic estimator, the stochastic models, and a double differenced phase range processing routine. Thus, no modifications to the original GEODYNII software were required. A schematic of the development is shown. The observational data are edited in the preprocessor and the data are passed to GEODYNII as one of its standard data types. A reference orbit is determined using GEODYNII as a batch least-squares processor and the GEODYNII measurement partial (FTN90) and variational (FTN80, V-matrix) files are generated. These two files along with a control statement file and a satellite identification and mass file are passed to the filter/smoother to estimate time-varying parameter states at each epoch, improved satellite initial elements, and improved estimates of constant parameters

Differences in Preventable Cardiovascular-Related Versus Unavoidable Occupational Causes of Firefighter Fatalities on Duty

Background: Firefighters across the United States face high fatality rates in the line of duty of which many are likely related to preventable cardiovascular risk factors. Objectives: To assess differences in firefighter cardiovascular-related versus unavoidable occupational-related fatalities by career status, age, smoking, obesity, and hypertension. Methods: We used an exploratory, comparative secondary data analysis design. We extracted data from a national database of deceased firefighters over 14 years. Variables extracted were career status, age, smoking, obesity, and hypertension as well as the reason for death while on duty (i.e., cardiovascular-related or unavoidable occupational-related death). Data were analyzed using Chi-Square to compare cardiovascular-related versus unavoidable occupational-related fatalities among the variables with significance set at 0.05. Results: In a sample population of 984 deceased firefighters nationwide, we found that career versus volunteer position status (χ2 = 1.14, p=0.56) did not significantly affect cardiovascular- related fatality outcomes compared to unavoidable occupational-related outcomes. Significantly more firefighter with increased age (χ2 = 176.16, p\u3c0.001), who smoked (χ2 = 10.91, p=0.001), had increased BMI (χ2 = 10.91, p=0.001), specifically obesity (χ2 =13.14, p\u3c0.001), and hypertension (χ2 =84.42, p\u3c0.001), had cardiovascular-related fatalities compared to those with unavoidable occupational-related fatalities. Conclusions: Our study demonstrated significant differences related to increased age, smoking, increased BMI, obesity, and hypertension in relation to increased cardiovascular fatalities in firefighters compared to unavoidable occupational-related fatalities. Our findings support the development of cost-effective nurse-practitioner (NP) led preventative health programs aimed at reducing cardiovascular-related fatalities in the fire service

GEODYN programmer's guide, volume 2, part 2

A computer program for executive control routine for orbit integration of artificial satellites is presented. At the beginning of each arc, the program initiates required constants as well as the variational partials at epoch. If epoch needs to be reset to a previous time, the program negates the stepsize, and calls for integration backward to the desired time. After backward integration is completed, the program resets the stepsize to the proper positive quantity

Is the slope of the intrinsic Baldwin effect constant?

We investigate the relationship between emission-line strength and continuum luminosity in the best-studied nearby Seyfert 1 galaxy NGC5548. Our analysis of 13 years of ground-based optical monitoring data reveals significant year-to-year variations in the observed H-beta emission-line response in this source. More specifically, we confirm the result of Gilbert and Peterson (2003) of a non-linear relationship between the continuum and H-beta emission-line fluxes. Furthermore, we show that the slope of this relation is not constant, but rather decreases as the continuum flux increases. Both effects are consistent with photoionisation model predictions of a luminosity-dependent response in this line.Comment: 9 pages, 6 figures, accepted for publication in MNRA