Machine tests slow-speed sliding friction in high vacuum

Testing machine that operates without any lubrication of the machine elements within the vacuum chamber measures static friction and sliding friction at very low speeds. Moving parts are held to a minimum to simplify operation in the vacuum chamber

Trends in environmentally induced spacecraft anomalies

The Spacecraft Anomaly Data Base was useful in identifying trends in anomaly occurrence. Trends alone do not provide quantitative testimony to a spacecraft's reliability, but they do indicate areas that command closer study. An in-depth analysis of a specific anomaly can be expensive and difficult without access to the spacecraft. Statistically verified anomaly trends can provide a good reference point to begin anomaly analysis. Many spacecraft experience an increase in anomalies during the period of several days centered on the solar equinox, a period that is also correlated with sun eclipse at geostationary altitude and an increase in major geomagnetic storms. Increase anomaly occurrence can also be seen during the local time interval between midnight and dawn. This local time interval represents a region in Earth's near space that experiences an enhancement in electron plasma density due to a migration from the magnetotail during or following a geomagnetic substorm

What’s Love Got to Do with It?

The life and work of student life professionals provide the glue in the academy. Being attentive to students’ health, well-being, success, and leadership development is what we do. It is what keeps the heart of our institutions beating. While dedication to this field requires passion, it can also run us dry. Love for the profession and love for oneself are essential to be whole, resilient professionals and human beings. Professional development includes personal development. This article is both a scholarly personal narrative and a call to action. It weaves the voices of a young professional and her mentor through their own journeys of discovery with research in the importance of heart in higher education. This article offers insight about the need to integrate the essential inner work of self-love into our profession

Attitude motion of a non-attitude-controlled cylindrical satellite

In 1985, two non-attitude-controlled satellites were each placed in a low earth orbit by the Scout Launch Vehicle. The satellites were cylindrical in shape and contained reservoirs of hydrazine fuel. Three-axis magnetometer measurements, telemetered in real time, were used to derive the attitude motion of each satellite. Algorithms are generated to deduce possible orientations (and magnitudes) of each vehicle's angular momentum for each telemetry contact. To resolve ambiguities at each contact, a force model was derived to simulate the significant long-term effects of magnetic, gravity gradient, and aerodynamic torques on the angular momentum of the vehicles. The histories of the orientation and magnitude of the angular momentum are illustrated

CHARACTER ASSESSMENT, GENUS LEVEL BOUNDARIES, AND PHYLOGENETIC ANALYSES OF THE FAMILY RHACOPHORIDAE:: A REVIEW AND PRESENT DAY STATUS

The first comprehensive phylogenetic analysis of the family Rhacophoridae was conducted by Liem (1970) scoring 81 species for 36 morphological characters. Channing (1989), in a reanalysis of Liem’s study, produced a phylogenetic hypothesis different from that of Liem. We compared the two studies and produced a third phylogenetic hypothesis based on the same characters. We also present the synapomorphic characters from Liem that define the major clades and each genus within the family. Finally, we summarize intergeneric relationships within the family as hypothesized by other studies, and the family’s current status as it relates to other ranoid families

A study of radiation environment in space and its biological effects

Biological effects on man in space resulting from galactic and solar cosmic radiation are discussed. Importance of secondary ions which contribute to galactic cosmic radiation hazards is analyzed. Mathematical model to show rate of production of secondary ions of given atomic number at various points in absorber is presented

Galactic cosmic ray heavy primary secondary doses

Results of a calculation which estimates the heavy primary secondary doses from cosmic ray interaction data are reported. The incident galactic cosmic ray heavy primary spectrum is represented as the sum of helium, nitrogen, magnesium, and iron components. The incident iron nuclei are allowed to fragment into lesser Z secondaries, which are assumed to travel in the same direction and start with the same energy per nucleon as the interacting primary. The total emergent particle energy spectra and dose are then presented for the galactic heavy primary spectrum incident on aluminum and tissue slabs. The importance of the fragmentation parameters assumed is also evaluated. The total dose from the heavy primaries and their secondaries is found to be reduced by only a factor of two in 20 g/sq cm of shielding

Attitudes towards lesbians and gay men and support for lesbian and gay human rights among psychology students

A questionnaire comprising two scales, the short form of the Attitudes Towards Lesbians and Gay Men Scale (ATLG-S; Herek, 1984) and the newly devised Support for Lesbian and Gay Human Rights Scale (SLGHR) were administered to 226 students taking undergraduate psychology courses at universities in the United Kingdom, to assess their attitudes towards lesbians and gay men, and their level of support for lesbian and gay human rights. The results indicated that whilst only a small percentage of respondents expressed negative attitudes towards lesbians and gay men on the ATLG-S, the sample as a whole did not overwhelmingly support lesbian and gay human rights. The lack of support for lesbian and gay human rights is discussed in relation to its implications for psychology students as future practitioners and policy makers. </p