A three‐axis short‐period seismometer has been operating on the surface of Mars in the Utopia Planitia region since September 4, 1976. During the first 5 months of operation, approximately 640 hours of high‐quality data, uncontaminated by lander or wind noise, have been obtained. The detection threshold is estimated to be magnitude 3 to about 200 km and about 6.5 for the planet as a whole. No large events have been seen during this period, a result indicating that Mars is less seismically active than earth. Wind is the major source of noise during the day, although the noise level was at or below the sensitivity threshold of the seismometer for most of the night during the early part of the mission. Winds and therefore the seismic background started to intrude into the nighttime hours starting on sol 119 (a sol is a Martian day). The seismic background correlates well with wind velocity and is proportional to the square of the wind velocity, as is appropriate for turbulent flow. The seismic envelope power spectral density is proportional to frequency to the −0.66 to −0.90 power during windy periods. A possible local seismic event was detected on sol 80. No wind data were obtained at the time, so a wind disturbance cannot be ruled out. However, this event has some unusual characteristics and is similar to local events recorded on earth through a Viking seismometer system. If it is interpreted as a natural seismic event, it has a magnitude of 3 and a distance of 110 km. Preliminary interpretation of later arrivals in the signal suggest a crustal thickness of 15 km at the Utopia Planitia site which is within the range of crustal models derived from the gravity field. More events must be recorded before a firm interpretation can be made of seismicity or crustal structure. One firm conclusion is that the natural background noise on Mars is low and that the wind is the prime noise source. It will be possible to reduce this noise by a factor of 103 on future missions by removing the seismometer from the lander, operation of an extremely sensitive seismometer thus being possible on the surface.
A three-axis short-period seismometer is now operating on Mars in the Utopia Planitia region. The noise background correlates well with wind gusts. Although no quakes have been detected in the first 60 days of observation, it is premature to draw any conclusions about the seismicity of Mars. The instrument is expected to return data for at least 2 years.
The purposes of this study were to ascertain the extent to which students with physical handicaps have clothing attitudes that differ from able‐bodied students, and to investigate the relationship between self‐concept and clothing attitudes. Data were collected from 35 handicapped and 76 able‐ bodied university students. Handicapped students were defined as those who had orthopedic dis abilities and were confined to wheelchairs. The clothing attitude variables were appearance, fash ion, management, comfort, and durability. There were clothing attitude differences between hand icapped and able‐bodied students for all variables except appearance. Handicapped students had consistently lower clothing attitude scores on all variables studied. There were significant differ ences between men and women students on all clothing attitude variables regardless of physical condition, with women indicating a more positive attitude on each of the variables. There was not a significant difference in self‐concept scores between the handicapped and able‐bodied students, nor was a statistically significant relationship identified between the clothing variables and self‐ concept scores.
An unusually rugged highly sensitive and inexpensive bubble tiltmeter has been designed, tested, and built in quantity. These tiltmeters are presently used on two volcanoes and an Alaskan glacier, where they continuously monitor surface tilts of geological interest. This paper discusses the mechanical, thermal, and electric details of the meter, and illustrates its performance characteristics in both large (> 10-4 radian) and small (< 10-6 radian) tilt environments. The meter's ultimate sensitivity is better than 2 X 10-8 radians rms for short periods (hours), and its useful dynamic range is greater than 10 4 • Included is a short description of field use of the instrument for volcano monitoring.
Over the past decade, empowerment evaluation has demonstrated its worth as a practical and valuable alternative to traditional program evaluation methodologies. Following a brief overview of the development of empowerment evaluation, we outline its 10 underlying principles and the three key steps involved in conducting an empowerment evaluation. A preliminary case study on our use of this methodology to evaluate the Good Start Breakfast Club program is presented. The Australian Red Cross operates this program in nearly 100 primary schools around Australia with sponsorship and support from the Sanitarium Health Food Company and other organisations. This case study highlights the potential effectiveness of empowerment evaluation in improving and assessing the impacts of other public health and community-based programs in Australia and some of the lessons we have learned so far from using this methodology. We identify strengths and limitations of empowerment evaluation and argue that a more critical approach is required to avoid the idealism that tends to underpin this approach. We suggest that greater attention needs to be paid to the communicative and relational dimensions of empowerment evaluation in order to increase its effectiveness.
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