Retransmission of water resources data using the ERTS-1 data collection system

There are no author-identified significant results in this report

Analysis and geological interpretation of gravity data from GEOS-3 altimeter

A number of detailed gravimetric geoids of portions of the world's oceans from marine gravity measurements were constructed. The geoids were constructed by computing 1 x 1 deg or 10 x 10 deg averages of free-air anomaly data and subtracting these values from currently used satellite derived Earth models. The resulting difference gravity anomalies are then integrated over a sphere using a simplified form of Stoke's equation to obtain a difference geoid. This difference geoid is added to the satellite derived model to obtain a 1 x 1 deg or 10 x 10 deg total gravimetric geoid. The geoid undulations are studied by comparison of the altimeter measurements with the morphology of the ocean floor. Utilizing a combination of altimetry data, gravity and seismic reflection data, geophysical models of the earth can be constructed

S-band antenna phased array communications system

The development of an S-band antenna phased array for spacecraft to spacecraft communication is discussed. The system requirements, antenna array subsystem design, and hardware implementation are examined. It is stated that the phased array approach offers the greatest simplicity and lowest cost. The objectives of the development contract are defined as: (1) design of a medium gain active phased array S-band communications antenna, (2) development and test of a model of a seven element planar array of radiating elements mounted in the appropriate cavity matrix, and (3) development and test of a breadboard transmit/receive microelectronics module

Surface chemistry of major rock types of Sonora Pass Test Site, California

Chemical study of selected rock samples tabulated as oxide percentage

JPL microwave experiment support

Geological parameter effects on remote microwave radiometer response

Ground data investigations Mt. Lassen, site 56-mission 76

Microwave radiometry and infrared photography for meteorological dat

An evaluation of the first year experience from the mature students' perspective; a multi-institutional comparison

This study investigates the experiences of mature students across three higher education institutions in the UK. The issues arising are of relevance to academics who are involved in widening participation and in evaluating support in their own programmes for the diversity of students. The sample includes mature students from programmes in Health, where mature students form a majority, and in Business, where mature students formed a minority. Focus groups were used to gain access to student perspectives on expectations, motivations, sacrifices, transitions, induction, programmes and assessment. The findings include misleading information that did not acknowledge the particular concerns and needs of mature students, induction processes that were not experienced as inclusive by mature students, and varying experiences of support but overall the institutional context was significant

Learning through research: the first year experience from the mature students perspective

This collaborative work from St Martin’s College, Salford and Middlesex Universities brings together experiences of mature students, (21+ years of age on entry), in a phenomenological piece of research identifying the different ways in which they feel supported in their undergraduate studies. There is particular value to the collaborative aspect of this research as it pulls together the differences in management and structures from a higher education college, a pre-1992 and post-1992 institutions. This paper aims to highlight the findings of the research at a point in time to feature the concerns of mature students on entering and the transition into HE, to demonstrate what mature students attribute to encouraging them to succeed and persist in their studies, learning ‘what works’ type strategies from the three institutions and devising new strategies to support not only this particular group of students, but all during their undergraduate studies

Oxygen diffusion and reactivity at low temperature on bare amorphous olivine-type silicate

The mobility of O atoms at very low temperatures is not generally taken into account, despite O diffusion would add to a series of processes leading to the observed rich molecular diversity in space. We present a study of the mobility and reactivity of O atoms on an amorphous silicate surface. Our results are in the form of RAIRS and temperature-programmed desorption spectra of O2 and O3 produced via two pathways: O + O and O2 + O, investigated in a submonolayer regime and in the range of temperature between 6.5 and 30 K. All the experiments show that ozone is formed efficiently on silicate at any surface temperature between 6.5 and 30 K. The derived upper limit for the activation barriers of O + O and O2 + O reactions is 150 K/kb. Ozone formation at low temperatures indicates that fast diffusion of O atoms is at play even at 6.5 K. Through a series of rate equations included in our model, we also address the reaction mechanisms and show that neither the Eley Rideal nor the Hot atom mechanisms alone can explain the experimental values. The rate of diffusion of O atoms, based on modeling results, is much higher than the one generally expected, and the diffusive process proceeds via the Langmuir-Hinshelwood mechanism enhanced by tunnelling. In fact, quantum effects turn out to be a key factor that cannot be neglected in our simulations. Astrophysically, efficient O3 formation on interstellar dust grains would imply the presence of huge reservoirs of oxygen atoms. Since O3 is a reservoir of elementary oxygen, and also of OH via its hydrogenation, it could explain the observed concomitance of CO2 and H2O in the ices.Comment: 28 pages, 14 figure

Improving the Functional Control of Aged Ferroelectrics using Insights from Atomistic Modelling

We provide a fundamental insight into the microscopic mechanisms of the ageing processes. Using large scale molecular dynamics simulations of the prototypical ferroelectric material PbTiO3, we demonstrate that the experimentally observed ageing phenomena can be reproduced from intrinsic interactions of defect-dipoles related to dopant-vacancy associates, even in the absence of extrinsic effects. We show that variation of the dopant concentration modifies the material's hysteretic response. We identify a universal method to reduce loss and tune the electromechanical properties of inexpensive ceramics for efficient technologies.Comment: 6 pages, 3 figure