Isolation characteristics of space telescope suspension systems Final technical report

Vibration isolation tests of spring, hysteresis, and magnetic suspension systems for spaceborne telescope

Design and testing of a magnetic suspension and damping system for a space telescope

The basic equations of motion are derived for a two dimensional, three degree of freedom simulation of a space telescope coupled to a spacecraft by means of a magnetic suspension and isolation system. The system consists of paramagnetic or ferromagnetic discs confined to the magnetic field between two Helmholtz coils. Damping is introduced by varying the magnetic field in proportion to a velocity signal derived from the telescope. The equations of motion are nonlinear, similar in behavior to the one-dimensional Van der Pol equation. The computer simulation was verified by testing a 264-kilogram air bearing platform which simulates the telescope in a frictionless environment. The simulation demonstrated effective isolation capabilities for disturbance frequencies above resonance. Damping in the system improved the response near resonance and prevented the build-up of large oscillatory amplitudes

THE INFRARED SPECTRUM OF SINGLE CRYSTALS OF ICE

Author Institution: The Harrison M. Randall Laboratory of Physics, University of MichiganSingle crystals of ice have been grown $2 \times 6$ cm in area and of two different thicknesses viz., 0.023 cm and approximately 1 cm. Absorption bands were studied at 1.09, 1.275, 1.505, 1.65, 2.01, 2.38, and 2.53 $\mu$, using polarized radiation with the electric vector parallel and perpendicular to the optic axis of the single crystal. Within the limits of experimental error, no dichroism was observed in any of these bands. This result is in agreement with recent observations by Ellis and $Vanderberg^{1}$ and disagrees with earlier observations by $Plyler,^{2}$ who reported marked dichroism for the bands at 1.09 and 1.275 $\mu$. The reflection spectrum of the thicker single crystal was also obtained in the region of 3 $\mu$, where two of the fundamental frequencies are located. Again no dichroism was observed. These results lend support to the $Pauling^{3}$ model for ice in the temperature range studied ($-27^\circ C$ to $-100^\circ C$)

Older Women's Fears Of Violence: The Need for Interventions that Enable Active Ageing

Women’s fear of violence can impact negatively on their active participation in life. An ageing survey conducted with 2620 Australian respondents aged 50 to 90 years examined aspects of work, learning, social, spiritual and emotional status, health, vision, home, life events, demographics, and asked an open ended question about what being actively engaged in life meant. Ordinal regression was carried out on two dependent variables: wanting and needing to learn to discourage violence. Analyses found that as women’s age increased, those on lower incomes were more likely than others to say they needed to learn how to discourage violence against them. This paper investigates the variables associated with the findings - transport, finances, news media, home safety, and reduced social interactions. Results highlight the importance of understanding women’s fear in the context of personal and social issues, and the need to provide learning opportunities to improve safety and social engagement

Neo-liberalism and the future of place marketing

Place marketing of cities tends to be seen as a pragmatic rather than a political activity aimed at bringing prosperity to localities. It is argued here that the reverse is the case: place marketing is an essentially political activity that demonstrates different political, or more accurately, class settlements by its impact upon cities. The political shift to neo-liberalism ended the post-war social democratic settlement and ushered in a new era for place marketing. Place marketing was an integral part of that settlement. It was particularly associated with gentrification which, it is argued, is a political strategy by which neo-liberalism takes control of the city. Place marketing, however, reached its limits by the end of the long boom – economic crisis is nothing more than the impact of the cumulative limits of that period. But now that crisis has discredited neo-liberalism it is unlikely that the place marketing that characterized the last twenty five years will remain. If place marketing symbolises different political settlements then the politics that emerges out of this crisis will generate another type of place marketing