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Using the Spreadsheet as a Tool for Teaching the Fundamentals of Engineering
This paper will demonstrate how the electronic spreadsheet has been used in a freshman level Fundamentals of Engineering course to prepare students for maximizing their analytical skills with the most ubiquitous analytical tool available today.Cockrell School of Engineerin
An expert system to analyze high frequency dependent data for the space shuttle main engine turbopumps
The prototype expert system ADDAMX identifies selected sinusoid frequencies from spectral data graphs as speed frequencies and harmonics from each turbopump, frequency feed through from one turbopump to another, frequencies generated by turbopump bearings, pseudo 3N for the phase 2 high pressure fuel turbopump, and electrical noise. ADDAMX does the analysis in an interactive or batch mode and the results can be displayed on the screen or hardcopy
A comparison of measured and theoretical predictions for STS ascent and entry sonic booms
Sonic boom measurements have been obtained during the flights of STS-1 through 5. During STS-1, 2, and 4, entry sonic boom measurements were obtained and ascent measurements were made on STS-5. The objectives of this measurement program were (1) to define the sonic boom characteristics of the Space Transportation System (STS), (2) provide a realistic assessment of the validity of xisting theoretical prediction techniques, and (3) establish a level of confidence for predicting future STS configuration sonic boom environments. Detail evaluation and reporting of the results of this program are in progress. This paper will address only the significant results, mainly those data obtained during the entry of STS-1 at Edwards Air Force Base (EAFB), and the ascent of STS-5 from Kennedy Space Center (KSC). The theoretical prediction technique employed in this analysis is the so called Thomas Program. This prediction technique is a semi-empirical method that required definition of the near field signatures, detailed trajectory characteristics, and the prevailing meteorological characteristics as an input. This analytical procedure then extrapolates the near field signatures from the flight altitude to an altitude consistent with each measurement location
Geometric Morphometrics of Gary Dart Points from the Davy Crockett National Forest
Three-dimensional scans of Gary dart points recovered from the Davy Crockett National Forest are employed in tests of basal morphology by site, size (allometry), and asymmetry. Variability in basal morphology for Gary points from sites on the Davy Crockett National Forest is presented and compared to specimens from the published type books. The hypothesis that Gary basal morphology differs between sites containing Woodland-era sand temped ceramics and those where no sand tempered ceramics were recovered is then tested and the results discussed
Optical Monitoring of Quasars: I. Variability
We present an analysis of quasar variability from data collected during a
photometric monitoring of 50 objects carried out at CNPq/Laboratorio Nacional
de Astrofisica, Brazil, between March 1993 and July 1996. A distinctive feature
of this survey is its photometric accuracy, ~ 0.02 V mag, achieved through
differential photometry with CCD detectors, what allows the detection of faint
levels of variability. We find that the relative variability, delta = sigma /
L, observed in the V band is anti-correlated with both luminosity and redshift,
although we have no means of discovering the dominant relation, given the
strong coupling between luminosity and redshift for the objects in our
sample.We introduce a model for the dependence of quasar variability on
frequency that is consistent with multi-wavelength observations of the nuclear
variability of the Seyfert galaxy NGC 4151. We show that correcting the
observed variability for this effect slightly increases the significance of the
trends of variability with luminosity and redshift. Assuming that variability
depends only on the luminosity, we show that the corrected variability is
anti-correlated with luminosity and is in good agreement with predictions of a
simple Poissonian model. The energy derived for the hypothetical pulses, ~
10^50 erg, agrees well with those obtained in other studies. We also find that
the radio-loud objects in our sample tend to be more variable than the
radio-quiet ones, for all luminosities and redshifts.Comment: 17 pages, 12 figures, accepted for publication in MNRAS (uses MNRAS
style
Correlation of predicted and measured sonic boom characteristics from the reentry of STS-1 orbiter
Characteristics from sonic boom pressure signatures recorded at 11 locations during reentry of the Space Shuttle Orbiter Columbia are correlated with characteristics of wind tunnel signatures extrapolated from flight altitudes for Mach numbers ranging from 1.23 to 5.87. The flight pressure signature were recorded by microphones positioned at two levels near the descent groundtrack along the California corridor. The wind tunnel signatures used in theoretical predictions were measured using a 0.0041-scale model Orbiter. The mean difference between all measured and predicted overpressures is 12 percent from measured levels. With one exception, the flight signatures are very similar to theoretical n-waves
Control optimization of a lifting body entry problem by an improved and a modified method of perturbation function
A study of the solution problem of a complex entry optimization was studied. The problem was transformed into a two-point boundary value problem by using classical calculus of variation methods. Two perturbation methods were devised. These methods attempted to desensitize the contingency of the solution of this type of problem on the required initial co-state estimates. Also numerical results are presented for the optimal solution resulting from a number of different initial co-states estimates. The perturbation methods were compared. It is found that they are an improvement over existing methods
A Web Design Curriculum for At-Risk Students
Students today deal emotionally, physically and socially with many negative influences in their lives. Too frequently they are besieged by violent images, the propagation of illegal drug usage among friends and family as well as other negative environmental influences. These influences create barriers that inhibit student learning and cause students to pull away from friends, teachers and school. The implementation of a web design curriculum will help provide struggling students an opportunity to reconnect with school through the use of technology. The web design curriculum lessons also provide activities that address bullying, harassment, drug and alcohol abuse, tobacco usage, suicide and sexual harassment. These thought provoking activities can assist students make good life decisions
9/11/73: The Chilean Way to Socialism Hits a Dead End
Salvador Allende and his political coalition hoped to change Chile\u27s social and economic system through peaceful means. This paper analyzes why opposition groups protested new policies while other groups used violence to disrupt and later overthrow Allende\u27s government. Included among the latter are the Chilean military and U.S. intelligence agencies. The paper also examines Allende\u27s death and compares conflicting versions of this tragedy
Medication mismanagement among elderly in Starr County
Given the current and projected rises in prescription drug use among the elderly in the United States and the current and projected rises in prescription drug costs, this research attempts to examine this national trend within the specific context of poverty and rurality manifested in Starr County, Texas. Starr County offers an ideal naturalistic laboratory for examining demographic predictors for improper medication use in the United States, poverty and rural residence. Hence within this context of poverty and rural location, the following questions are posited for investigation in Starr County. To what extent do high drug costs and low incomes hinder the elderly in following prescription regimens and physician recommendations for obtaining and maintaining optimal health and what strategies do the elderly in Starr County use and implement in order to achieve a balance between adherence to a proper medication regimen necessary to maintain their health and adherence due to poverty
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