Merits of flywheels for spacecraft energy storage

Flywheel energy storage systems which have a very good potential for use in spacecraft are discussed. This system can be superior to alkaline secondary batteries and regenerable fuel cells in most of the areas that are important in spacecraft applications. Of special importance, relative to batteries, are lighter weight, longer cycle and operating life, and high efficiency which minimizes solar array size and the amount of orbital makeup fuel required. Flywheel systems have a long shelf life, give a precise state of charge indication, have modest thermal control needs, are capable of multiple discharges per orbit, have simple ground handling needs, and have characteristics which would be useful for military applications. The major disadvantages of flywheel energy storage systems are that: power is not available during the launch phase without special provisions; and in flight failure of units may force shutdown of good counter rotating units, amplifying the effects of failure and limiting power distribution system options; no inherent emergency power capability unless specifically designed for, and a high level of complexity compared with batteries. The potential advantages of the flywheel energy storage system far outweigh the disadvantages

Battery-package design provides for cell cooling and constraint

Lightweight battery-package provides for even cooling of individual alkaline cells, constraint against cell expansion, and convenient placement of cells. The battery package also provides for venting of the cells and includes instrumentation to measure cell temperature, pressure, and voltage

Special Test Methods for Batteries

Various methods are described for measuring heat generation in primary and secondary batteries as well as the specific heat of batteries and cell thermal conductance. Problems associated with determining heat generation in large batteries are examined. Special attention is given to monitoring temperature gradients in nickel cadmium cells, the use of auxiliary electrodes for conducting tests on battery charge control, evaluating the linear sweep of current from charge to discharge, and determining zero current voltage. The fast transient behavior of batteries in the microsecond range, and the electrical conductance of nickel sinters in the thickness direction are also considered. Mechanical problems experienced in the vibration of Ni-Cd batteries and tests to simulate cyclic fatigue of the steel table connecting the plates to the comb are considered. Methods of defining the distribution of forces when cells are compressed during battery packaging are also explored

Nickel cadmium cell designs negative to positive material ratio and precharge levels

A review is made of the factors affecting the choices of negative-to-positive materials ratio and negative precharge in nickel-cadmium cells. The effects of these variables on performance are given, and the different methods for setting precharge are evaluated. The effects of special operating requirements on the design are also discussed

Analytical modeling of battery cycle life

An analytical model related to the physical and chemical processes involved in battery wear and failure is discussed. The model is described using the data from the Crane tests

Global large scale structures in the F region

Measurements of neutral densities, temperatures and ion density and temperature by the Atmosphere Explorer C and E satellites exhibit fluctuations made up of coherent waves of scale size from hundreds to thousands of kilometers. The fluctuations in the AE-C data are found at times of low magnetic activity to extend from the auroral region in one hemisphere across the equator to the corresponding region in the other hemisphere with little change in apparent wavelength. The fluctuations in the AE-E data similarly exhibit at times of low magnetic activity nearly uniform wave structure encircling the equatorial belt. Typical examples of waves of more than 1000 km apparent wavelength in both the AE-C and AE-E data are presented. These observations during quiet times may be explained by a system of quasi-stationary waves excited by the auroral belts that are distributed about the Earth possibly with tidal or sub-tidal periods and scale lengths determined by the structure of the belts. According to this interpretation, Traveling Ionospheric Disturbance (TID's) are manifestations of transient wave systems moving past a ground observatory that result from changes in magnetic activity with periods and scale sizes associated with the regions of enhanced auroral activity. Some evidence suggesting tidal-like stationary waves from the Millstone Hill incoherent scatter radar is presented

Let’s Change the Record: Women Only Studio Lock-in: An experiment in audio education and transforming the recording studio space within a university setting

There is a need to radically address the issues facing those identifying as female in the audio technology and music production space. This paper reports on an experiment in teaching and learning in a women* only recording studio. By 2016 the topic of sexism and misogyny in the music industry reached a crescendo, from Bjork talking in interviews about made ‘invisible’ as the producer of her own music1 to Annie Mac on BBC Radio1talking about the lack of female acts and female Dj’s at festivals. Annie Mac’s show (BBC Radio 1, March 2016)2 on the subject of women in the music industry pointed out that women make up less than 16% of writers registered at PRS3 and less than 15% of performers booked to play UK festivals. As the course leader of the MA Music Business Management, a music manager and head of business affairs at a music label (for over two decades), I have first-hand experience of the inequality and lack of diversity within the wider music industries from recording studios to publishing houses and beyond. These new conversations in the media and on line gave us the opportunity to demand that we addressed some of these core issues. So on the 21st and 22nd of May 2016 a group of twenty-two women*4 took over a state of the art recording studio with 48 inputs / 48 outputs, known as D9 situated on the Harrow Campus at the University of Westminster School of Media, Art and Design. The aim of the ‘studio lock in’ event, was to confront head on the issues of gender dynamics in recording studio environments in the hope that the event might kick start a chain reaction, that would include the department taking seriously the challenges faced by female identifying persons. Participants included students from Leeds College of Music, City of Westminster College, Westminster’s MA Music Business Management, Goldsmith College and respondents from an advert put out on Facebook who had a range of experience and ability, from Goldsmiths College post-graduate audio production students with a high skill level to absolute beginners who don’t know how to get started. Studio workshop sessions were punctuated by guest lectures all of whom told their stories, shared their advice and skills. We didn’t feel like we even scratched the surface of what could be achieved in a women-only studio environment. We found that the exclusion of men was incredibly conducive to real learning. We had been inspired by the work of the City College of San Francisco’s recording arts programme which in 2003 launched Women’s Audio Mission5, the first and still the only organisation in the world that is providing specialised training for women. Since the founding of Women’s Audio Mission, female enrolment on the City College’s recording arts program has gone from 12% to 43%, which is now the highest percentage of female enrolment in any recording arts institution in the U.S. Unfortunately, we don’t have figures to compare in the UK, but certainly here at the University of Westminster we have never exceeded 15% female enrolment on our audio production courses

Orbital currents in the Colle-Salvetti correlation energy functional and the degeneracy problem

Popular density functionals for the exchange-correlation energy typically fail to reproduce the degeneracy of different ground states of open-shell atoms. As a remedy, functionals which explicitly depend on the current density have been suggested. We present an analysis of this problem by investigating functionals that explicitly depend on the Kohn-Sham orbitals. Going beyond the exact-exchange approximation by adding correlation in the form of the Colle-Salvetti functional we show how current-dependent terms enter the Colle-Salvetti expression and their relevance is evaluated. A very good description of the degeneracy of ground-states for atoms of the first and second row of the periodic table is obtained