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UK shows the way on cloud regulation

‘Regulating the cloud crowd’ (May 2013, http://bit.ly/eandt-reg-cloud) raises an interesting chicken-and-egg scenario regarding EC legislation proposals around cloud services, and individual countries taking the lead with their own policies. However, the UK government’s initiatives over the past couple of years have demonstrated a strong commitment to improving the way that public sector organisations use and procure IT services, and encouraging more to adopt the cloud for all its associated benefits while the EC continues to seek to establish standards.

For instance, in just over a year, the G-Cloud Framework has proven to be transformational, delivering a far greater choice of assured cloud services to the 30,000 UK public-sector organisations. The programme has facilitated a move away from a stagnant market dominated by inflexible incumbents, and opened it up to SMEs.

The Public Cloud First Policy, which mandates the procurement of all IT services via the G-Cloud, is a further sign of the UK government’s confidence in the Framework and also its ongoing commitment to greatly improve the use and procurement of IT within the public sector. The end goal is to both improve operational efficiency and dramatically reduce overheads within departments that have been affected by budget constraints.

Alexander Brown is correct in his assessment that “clients have to understand what they are buying... and precisely what they are going to get out of the deal”. The G-Cloud Framework delivers this level of transparency to public sector organisations, both in terms of assurance levels and pricing. The savings for the UK tax payer have been significant and represent massive savings for over-stretched departments struggling to deliver quality service in tough economic times.

While the EC considers its proposals, it would do well to follow the example set out by the UK government’s G-Cloud, which has already seen £22m worth of public sector spending through the Framework.

Phil Dawson
Chief executive officer, Skyscape Cloud Services


RMS power won’t go quietly

RH Pearson tells much, but not all, of the story of ‘RMS power’ (Letters, June 2013, http://bit.ly/eandt-letters-1305). In answer to his two questions, yes, some of us do try to correct the misconception, but no, it is not likely to be possible to kill it completely.

Explanations to young students and technicians are often hampered by the fact that their dear little brains have never been exposed to the horrors of calculus, in case it inhibits their ability to write free-form poetry.

Beyond ‘RMS power’, we have ‘music power’ or ‘dynamic headroom’, which reflects the fact that an audio amplifier with a Class AB or B (or most of the unofficial ones from E to Z) output stage and an unregulated power supply can deliver somewhat more power to its load for brief periods, until the supply voltage collapses to a steady-state value. But claims for music powers far in excess of reality abounded, and, of course, the two channels of a stereo product had their output powers added.

Next came ‘PMPO’, peak music power output, which was probably originally an imagined value, but later attempts were made to legitimise it as the power that resulted from the whole stored energy of the power supply being dumped into the load in 1 millisecond (or was that 1 nanosecond?). This results in a ‘20W stereo amplifier’ being fed from a 12V 1A plug-transformer.

In any case, the whole preoccupation with audio amplifier power is based on lack of understanding. Input power is relevant to loudspeakers (except horns and some rarer types) only in their role as poorly-designed room heaters. Even the boxes are lagged internally to prevent too much heat escaping! The radiated sound power is usually less than 5 per cent of the power that simply heats up the voice-coil. And because the impedance of the loudspeaker is a widely varying function of frequency, only resistive (normally) at two frequencies, the real input power is unknown. As sound radiators, loudspeakers are voltage-operated devices.

John Woodgate


Is space solar overcomplicated?

Space solar power seems an excellent idea as a solution to our energy needs (‘Beam it down’, May 2013, http://bit.ly/eandt-beam-down). Could I suggest a simplification though? Rather than convert the solar radiation to microwaves then beam them down to Earth and convert back to electricity (overall efficiency around 70 per cent and 200W per square metre), why not let the original solar radiation travel unimpeded to the Earth’s surface (efficiency around 70 per cent and 800W per square metre) where it can then be converted into electricity. Admittedly there are some additional losses, but without the substantial cost, complexity and maintenance problems associated with a space-based system, and able to use the ample areas of desert available.

Isn’t that what solar panels do, or am I missing something?

Sorry about being a bit sarcastic, but it does seem to be a very complicated solution to a simple problem. Already solar power can give 24/7 output - such as the Gemasolar 20MW installation built in 2011, while PV costs are rapidly falling. High-voltage DC power lines can efficiently transport the power to where it is needed. Space solar may be more efficient overall, but with far more free solar radiation than we could possibly use it is cost, not efficiency, that matters.

Rob Basto


Role models

In nearly 30 years of studying and working in engineering I have read so many articles suggesting ways of improving our status; many of which revolve about protecting the title ‘engineer’. To date, nothing has changed.

Maybe we should take another approach: the work of engineers touches every aspect of people’s lives; however, compared with the likes of lawyers, doctors and accountants they are rarely portrayed in the media and fiction. If they do appear they are often stereotyped as geeks or nerds - or, for women engineers, as butch and unfeminine.

I have never seen a soap opera character who is an engineer or a younger character in soap operas who aspires to study engineering at university. Sometimes characters are car mechanics, crane drivers, or electricians but as we all know these are technicians not engineers.

Popular media has a huge influence on our younger generation. I wonder if it would be benefical for soap writers to consider developing an attractive, well-off, continuously employed character who is an engineer.

Jackie Portman
By email


Airborne radar

In an interesting article on bi-static radar (‘Radar divides to conquer’, May 2013, http://bit.ly/eandt-radar-divides), Professor Hugh Griffiths is quoted as suggesting that future designs of UAVs could save precious weight and fuel by moving to multistatic architectures in which only the receiver needs to be airborne.

In 1957 Ferranti and The Bristol Aircraft Company were producing the Bloodhound surface to air missile. The target aircraft was illuminated by a ground-based radar and only the receiver was in the missile. Yes, only the receiver needs to be airborne for certain applications.

John Corbett CEng MIET
By email


Building bridges

I was working in Dallas when London Bridge was purchased by US entrepreneur Robert P McCulloch in 1967 and the link with Tower Bridge mentioned in Justin Pollard’s June 2013 Eccentric Engineer column was not completely mythical. The Dallas Times Herald reported the news on its front page with an accompanying picture of Tower Bridge. I pointed out the error but it was never clarified.

Stan Jones
Great Kingshill, Bucks



Tony Howarth’s experience of trying to develop his Africar (Interview, June 2013, http://bit.ly/eandt-Africar) is a perfect illustration of the old saying “The best is the enemy of the good”. If instead of trying to develop the perfect vehicle from scratch he had joined forces with an existing manufacturer, a reasonably suitable vehicle may perhaps have gone into quantity production decades ago.

There were a number of vehicles to choose from, not perfect by any means but all well proven in third world conditions. They were the original air-cooled VW Beetle, the Citroen 2CV, the Series 2/Series 3 Morris Oxford (built under licence as the Hindustan Ambassador), and the Russian Lada, which despite the many jokes was actually a tough and simple workhorse if it could be kept from rusting.

These cars were rough and mechanically straightforward and production should have been relatively cheap. There would have been compromise against Mr Howarth’s requirements but, as in most things, a compromise solution 30 years ago would have been better for Africa than absolute perfection still sometime in the future.

I now fear the opportunity has passed. Only the Hindustan remains in production and pressure groups with no real knowledge of sub-Saharan Africa will try to make it impossible for a vehicle, particularly a new design, that does not conform to ‘first world’ standards for safety and environmental impact, to be produced. Most cars built 30 years ago may have been unsuitable but could have been repaired with simple tools and facilities. Today’s models will tax support facilities to the limit.

DJ Garrett MIET
Comber, Co Down

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