Recent content by cepheus

Wouldn't we be able to predict the future if this was true?

One of the most fascinating implications of this proposed by Wheeler was that there were only one electron in existence traveling forwards in time until it is converted to a positron traveling backwards in time and so forth, providing the illusion of many particles. If this was true however we...

I suggest that power units should be standardised with respect to the fixture points, and module based (battery pack or hybrid). The position of the module is defined relative to the wheels and ramp so the module replacement can be largely automatic and shouldn't take longer than normal...

Well true, but there are just so many inefficiencies along the route to producing power, even before transport, storage then use in the fuel cell: I recall assessing a proposal for a hydrogen powered fuel cell tram! why not just use the electricity directly?

At what cost? I would like to see some evidence of this, do you mean economical for producing hydrogen? I recall seeing actual figures during the CUTE bus project I linked, which used local electroysis stations and the economics both in terms of energy and money was appalling!

I think the impact of a small bottle of water dopped from several hundred metres could be quite lethal even if wrapped in foam. However, there is no reason why small packets of antibiotics couldn't be tipped out this way, perhaps directly on the built up areas or at least parks, since I...

Well it was good on piling things up at the airport, but the boxes were not unpacked and people were not allowed in the airport. Haiti was within a few hunded miles of the nearest US base and not far from Florida and is therefore not typical. The design is really intended for the first few...

Interesting. Would these work in a strong wind, perhaps they could only drop within 100 metres of the target? I expect these may be expensive if applied to multiple small packages. I suppose even a designated spot would have to be 'secured' to prevent the package landing on anyone. Some...

My thoughts of late have been drawn towards the Haitian earthquake relief and how simple technical solutions could mitigate similar crisis in future disaster situations. I believe that it should be possible to develop a cheap and effective aid delivery system that could safely distribute...

Fuel cells are more expensive than batteries, hydrogen is more expensive than electricity, hydrogen is more expensive to transport than electricity. The only economic way of producing hydrogen is via steam reforming from natural gas so unless you sequester the CO2 it doesn't even reduce...

There are a some benefits with organic farming such as ecosystem diversity and soil and water quality. There are less benefits with greenhouse gases when calculated on a per unit food production basis and it could even be worse...

Well the link doesn't work but the wiki artcle suggests that Contra-rotating propellers have been found to be between 6% and 16% more efficient than normal propellers[1].

Isn't this a good idea when contra-rotating since it strightens out the airflow? I think aircraft manufacturers are considering this for future turboprop designs http://en.wikipedia.org/wiki/Contra-rotating_propellers

Isn't this principle normally applied to rotating cylinders and called the Magnus effect? Some ships and wind turbines have used it. I recall it was seriously considered as a supplement for conventional ship propulsion a few decades ago. The ship can evidently travel at a greater angle into...

Hi there How would you define pollution? the question is to ambiguous. the solution is vastly different between local/regional/global/water pollution. Using/buying less will generally reduce just about any type of pollution, although technological solutions vary widely.