1,333 research outputs found
George C. Baum – His Life, His Work, and His Relationship with Gettysburg College
There is a tablet in Gettysburg College’s Plank Gym, partially obscured by trash bags and stacks of materials and boxes, that reads, “THIS TABLET IS PLACED IN AFFECTIONATE MEMORY OF GEORGE CROLL BAUM, A.M., B.A., THE ARCHITECT OF THIS BUILDING, BY A GRATEFUL ALMA MATER.” These commemorative tablets are not rare at Gettysburg. In the same room as Baum’s tablet is one for Eddie Plank, the famed deadball-era hurler for the Philadelphia Athletics and member of the Major League Baseball Hall of Fame. Across the campus, there are tablets commemorating graduating classes, historic moments, and historic people. One could ask several pertinent questions: why does Baum, who is just one particular architect for the College, have a tablet? Was Plank Gym his only contribution to the College’s development? What else did Baum design? Perhaps more simply: who was George Croll Baum? [excerpt]
Course Information: Course Title: HIST 300: Historical Method Academic Term: Spring 2006 Course Instructor: Dr. Michael J. Birkner \u2772
Hidden in Plain Sight is a collection of student papers on objects that are hidden in plain sight around the Gettysburg College campus. Topics range from the Glatfelter Hall gargoyles to the statue of Eisenhower and from historical markers to athletic accomplishments. You can download the paper in pdf format and click View Photo to see the image in greater detail.https://cupola.gettysburg.edu/hiddenpapers/1027/thumbnail.jp
Pope John Paul II, the Assassination Attempt, and the Soviet Union
“The attempt to murder the pope remains one of the century’s great mysteries,” wrote Carl Bernstein and Marco Politti in their 1996 biography of Pope John Paul II. Indeed, the mystery has remained unsolved since the pope was shot and wounded on May 13, 1981. A recent investigation concluded that the Soviet government was the perpetrator, but the situation should be examined in a broader historical context. What actually happened on May 13, 1981? Was it the sole decision and action of Mehmet Ali Agca, who was expressing his opposition to “Western imperialist policies,” as he had written in a threatening letter to a newspaper in 1979? Or had “someone else commissioned him to carry it out,” as Pope John Paul II alleged in a memoir written in 2005?
Before evaluating the question from an historical standpoint, it is necessary to provide some background in order to establish a potential motive for the Soviet Union to support such an assassination attempt. Was Karol Wojtyla (the Pope’s birth name) really “[their] enemy,” as a party directive warned in 1979? Only then can we evaluate the Soviet Union’s involvement, or whether there was a conspiracy behind the attempted assassination of John Paul II at all. Finally, we should step back and look at the significance of the assassination attempt and the impact of the pope on the Cold War and Soviet dominance of Eastern Europe
The calculation of ionospheric absorption with modern computers
New outcomes are proposed for ionospheric absorption starting from the Appleton-Hartree formula, in its complete form. The range of applicability is discussed for the approximate formulae, which are usually employed in the calculation of non-deviative absorption coefficient. These results were achieved by performing a more refined approximation that is valid under quasi-longitudinal (QL) propagation conditions. The more refined QL approximation and the usually employed non-deviative absorption are compared with that derived from a complete formulation. Their expressions, nothing complicated, can usefully be implemented in a software program running on modern computers. Moreover, the importance of considering Booker’s rule is highlighted. A radio link of ground range D = 1000 km was also simulated using ray tracing for a sample daytime ionosphere. Finally, some estimations of the integrated absorption for the radio link considered are provided for different frequencies
Real Time 3D Ionospheric Modelling with Ray Tracing Application over Mediterranean Area
This poster deals with some practical examples of instantaneous 3D modelling of regional ionosphere, based on ionosondes data from the Istituto Nazionale di Geofisica
e Vulcanologia, INGV.
Characteristic anchor points have been chosen for each ionospheric region. These points are joint by an adaptive ionospheric profiler derived from the one used in
Autoscala. For the F2 region the anchor point is given by the real height hmF2 of the layer and its critical frequency foF2. These values are obtained basing on the
observed heights (hmF2ROME[OBS] and hmF2GIBILMANNA[OBS]) and critical frequencies (foF2ROME[OBS] and foF2GIBILMANNA[OBS]) of the F2 layer, which are compared with the corresponding monthly median given by CCIR maps using Shimazaki’s formulation.
The differences
dhmF2ROME = hmF2ROME[OBS] - hmF2ROME[CCIR]
dhmF2GIBILMANNA = hmF2 GIBILMANNA [OBS] - hmF2 GIBILMANNA [CCIR]
are thus computed and used in Kriging method to update the values given by CCIR maps.
For the F1 region the critical frequency is derived form a solar zenith angle dependent model adjusted to match the values of foF1 measured in Rome and Gibilmanna.
For the E region the height is set to 110 km, while the critical frequency is estimated by a standard solar zenith angle and solar activity dependent model.
The model produces as an output a 3D matrix which can be profitably used as an input for a Matlab/Fortran based ray tracing program recently developed at INGV
Electronic density contours and gravity waves
A campaign of ionospheric vertical sounding with an interval of 10 minutes between all the ionograms was performed in November 1995 in the station of Rome.
High-repetition soundings are more useful than the routine soundings for a more precise analysis of the MSTIDs. Isodensity contours of real height vs. time were obtained. The periods of oscillations observed and the upward phase propagation suggest the existence of gravity waves in the ionosphere
A Software for Automatic Scaling of foF2 and MUF(3000)F2 from Ionograms
A software for automatic scaling of critical frequency f0F2 and MUF(3000)F2 is presented. The program is designed to
scale the ionograms without using information on polarization and can be applied to both single antenna systems and
crossed antenna systems. A data set of 619 ionograms recorded at the ionospheric observatory of Rome has been used to
test the performance of the software. The test has been performed comparing the values obtained automatically with the
ones obtained by the standard manual method
Can the polarization tagging of the ionogram trace deceive autoscaling methods? The Learmonth case
This paper focuses on the problem of invalid O/X polarization tagging of an ionogram and
how this can affect ionogram autoscaling methods. To illustrate this problem, 623 ionograms recorded in March and April 2004 (days 080-105) by the digisonde 256 installed at Learmonth (22.3° S, 114.1° E) were considered. These ionograms, often characterized by very unreliable O/X
polarization tagging of the echoes because of unresolved antenna issues, have been autoscaled by both ARTIST 4.2 and Autoscala. Results of comparisons between automatically and manually scaled foF2 data are shown for both programs, considering as acceptable an autoscaled value that lies within 0.5 MHz of the manual value. Autoscala values of foF2 agree with the manually-scaled values for ~99% of ionograms, while ARTIST values of foF2 agree with the manually-scaled values for ~75% of ionograms. While ARTIST was coded on the assumption of valid polarization
tagging, the fact remains that it produces invalid results when equipment issues cause invalid tagging. Autoscaling procedures that do not use the polarization tagging will generally work better than ARTIST in such cases. However, these other procedures are susceptible to failure in other situations
Optimal alarm systems for FIAPARCH processes
In this work, an optimal alarm system is developed to predict whether a financial time series modeled via Fractionally Integrated Asymmetric Power ARCH (FIAPARCH) models, up/downcrosses some particular level and give an alarm whenever this crossing is predicted. The paper presents classical and Bayesian methodology for producing optimal alarm systems. Both methodologies are illustrated and their performance compared through a simulation study. The work finishes with an empirical application to a set of data concerning daily returns of the Sao Paulo Stock Market
Scintillation efficiency of liquid argon in low energy neutron-argon scattering
Experiments searching for weak interacting massive particles with noble gases
such as liquid argon require very low detection thresholds for nuclear recoils.
A determination of the scintillation efficiency is crucial to quantify the
response of the detector at low energy. We report the results obtained with a
small liquid argon cell using a monoenergetic neutron beam produced by a
deuterium-deuterium fusion source. The light yield relative to electrons was
measured for six argon recoil energies between 11 and 120 keV at zero electric
drift field.Comment: 21 pages, 19 figures, 4 table
Automatic interpretation of oblique ionograms
We present an algorithm for the identification of trace characteristics of oblique ionograms allowing determination of the Maximum Usable Frequency (MUF) for communication between the transmitter and receiver. The algorithm automatically detects and rejects poor quality ionograms. We performed an exploratory test of the algorithm using data from a campaign of oblique soundings between Rome, Italy (41.90 N, 12.48 E) and Chania, Greece (35.51 N, 24.01 E) and also between Kalkarindji, Australia (17.43 S, 130.81 E) and Culgoora, Australia (30.30 S, 149.55 E). The success of these tests demonstrates the applicability of the method to ionograms recorded by different ionosondes in various helio and geophysical conditions
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