An Analysis of Coast Guard HH-65 Engine Reliability: A Comparison of Malfunctions to Component Removals

The Coast Guard HH-65 helicopter experienced 31 in-flight loss of power incidents during FY 2003 and 21 during the first two months of FY 2003. Concurrent with this apparent decrease in reliability, the Coast Guard seeks ways to expand the HH- 65’s Airborne Use of Force capabilities as a result of the September 11th, 2001 terrorists’ attacks. This study is an exploratory, empirical analysis of engine and airframe component replacements as related to engine mishaps and reliability in the HH-65. We use contingency table analysis, ordinary least squares regression, and logistic regression to examine the mishap history and component replacement history of ten different HH-65 components from 1997 through March of 2003. Additionally, we examine the literature to determine the factors impeding improvements to the HH-65 powerplant. This study reveals three critical issues associated with the HH-65 powerplant, namely, lack of power reserve associated with the LTS-101-750, poor reliability associated with the fuel-control system, and excessive trouble removals due to excessive time between scheduled overhaul times. Moreover, we find lack of funding and political pressure forcing the Coast Guard toward a less than optimum fix that could adversely affect overall mission effectiveness and Homeland Security

Professional Materials Review

Supporting Struggling Readers. Barbara J. Walker. 1992

Reuseable Objects Software Environment (ROSE): Introduction to Air Force Software Reuse Workshop

The Reusable Objects Software Environment (ROSE) is a common, consistent, consolidated implementation of software functionality using modern object oriented software engineering including designed-in reuse and adaptable requirements. ROSE is designed to minimize abstraction and reduce complexity. A planning model for the reverse engineering of selected objects through object oriented analysis is depicted. Dynamic and functional modeling are used to develop a system design, the object design, the language, and a database management system. The return on investment for a ROSE pilot program and timelines are charted

Financial History

The considerable renewal of interest in all aspects of financial history over recent years provided one motivation for this new venture. Yet, the foundations for our specialism, which draws from both History and the Social Sciences, especially economics, have been laid by many. Some would point to continuity in our interest from the publication in the 1930s of jubilee banking history volumes, such as those written for British institutions by Gregory, and by Crick and Wadsworth. Further scholarly momentum came from the studies in comparative banking history undertaken by researchers inspired and brought together by Rondo Cameron from the mid-1960s. Upon these footings and others, financial history has since ‘taken off' to address an increasingly wider range of issues. This considerable broadening of the specialism, ironically, almost coincided with the decline and then the eventual demise in 1987 of the Revue Internationale d'Histoire de la Banque, founded in 1968. This is not the place to draw up a balance sheet of that journal, which has played a decisive role. Its demise, however, left a gap. Financial History Review aims not only to take up its cause, but also to widen the scope of publishing in the field - from banking to financial history - in order to offer the fullest possible support for continuing researc

Differential chemical abundance analysis of a 47 Tuc AGB star with respect to Arcturus

This study resolves a discrepancy in the abundance of Zr in the 47 Tucanae asymptotic giant branch star Lee 2525. This star was observed using the echelle spectrograph on the 2.3 m telescope at Siding Spring Observatory. The analysis was undertaken by calibrating Lee 2525 with respect to the standard giant star Arcturus. This work emphasises the importance of using a standard star with stellar parameters comparable to the star under analysis rather than a calibration with respect to the Sun (Koch & McWilliam 2008). Systematic errors in the analysis process are then minimised due to the similarity in atmospheric structure between the standard and programme stars. The abundances derived for Lee 2525 were found to be in general agreement with the Brown & Wallerstein (1992) values except for Zr. In this study Zr has a similar enhancement ([Zr/Fe] = +0.51 dex) to another light s-process element, Y ([Y/Fe] = +0.53 dex), which reflects current theory regarding the enrichment of s-process elements by nuclear processes within AGB stars (Busso et al. 2001). This is contrary to the results of Brown & Wallerstein (1992) where Zr was under-abundant ([Zr/Fe] = +0.51 dex) and Y was over-abundant ([Y/Fe] = +0.50 dex) with respect to Fe.Comment: 11 pages, 5 figures Accepted for publication in MNRA

Globular Cluster Formation in M82

We present high resolution mid-infrared (mid-IR; 11.7 and 17.65 micron) maps of the central 400 pc region of the starburst galaxy M82. Seven star forming clusters are identified which together provide ~ 15% of the total mid-IR luminosity of the galaxy. Combining the mid-IR data with thermal radio measurements and near- and mid-IR line emission, we find that these young stellar clusters have inferred masses and sizes comparable to globular clusters. At least 20% of the star formation in M82 is found to occur in super-star clusters.Comment: 12 pages including three color figures; accepted for publication in Ap

Presentation procedures in measuring emotion laterality via the auditory modality

For more than three decades cognitive neuroscientists have debated the lateralisation of emotion. Currently there are two theories in contention: the right hemisphere hypothesis and the valence hypothesis. The right hemisphere hypothesis is that all emotional are predominantly processed in the right cerebral hemisphere of the human brain while the valence hypothesis is that positive (or approachrelated) and negative (or withdrawal-related) emotions are processing in the left and right cerebral hemispheres respectively. In general listening studies aimed to measure the lateralisation of emotion have employed disparate presentation procedures resulting in inconsistent findings. The current study investigated the affective judgment of simple classes of auditory stimuli (e.g. tonal/atonal melodies) via three presentation procedures: monoaural (i.e. target with no competition), binaural (i.e. target with competing noise), and dichotic (i.e. target with competing melody). Overall, presentation procedure had a direct influence on observed asymmetry highlighting the need for consistency in listening studies aimed to measure the lateralisation of emotion

Spectral matching for abundances of 848 stars of the giant branches of the globular cluster {\omega} Centauri

We present the effective temperatures, surface gravities and abundances of iron, carbon and barium of 848 giant branch stars, of which 557 also have well-defined nitrogen abundances, of the globular cluster {\omega} Centauri. This work used photometric sources and lower resolution spectra for this abundance analysis. Spectral indices were used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. The 557-star subset was analyzed in the context of evolutionary groups, with four broad groups identified. These groups suggest that there were at least four main four periods of star formation in the cluster. The exact order of these star formation events is not yet understood. These results compare well with those found at higher resolution and show the value of more extensive lower resolution spectral surveys. They also highlight the need for large samples of stars when working with a complex object like {\omega} Cen.Comment: 12 pages, 14 figures, accepted for publication in MNRA