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Comment: Ah welcome to the 1960s (Score 1) 213

by prefec2 (#49369655) Attached to: Chinese Scientists Plan Solar Power Station In Space

This interesting idea and technological endeavor was proposed in the 1960s maybe it was also proposed before, but that is were I read first about it - in a book from the 1960s. Later they did not build it because it was so incredible expensive to get all the materials up, repair it in space, and keep its focus on the same spot on the ground. Next, they will figure out that placing panels on roofs is much more efficient even though it will not work in their metropolises as the air is too polluted. Anyway, they have enough free country side to go for it.

Comment: Good Code Metircs (Score 1) 294

by prefec2 (#49357733) Attached to: Ask Slashdot: What Makes Some Code Particularly Good?

There are several metrics which can help you to identify code which is not bad. One is cyclomatic complexity. Another are connectivity metrics going over the graph your code spans. For cyclomatic complexity there are good boundaries available. However, it is a complexity metric. And complexity is not the only thing which affects code quality. Other elements are labeling operations, such as methods, functions, and procedures. There is plenty of lit. available in the area of code comprehension.

Comment: Re:Pilots must remain in control (Score 1) 378

by prefec2 (#49356563) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

The interesting thing would be to find out which constellation is better pilots + computers or computers. For both sides you can come up with scenarios where only a human or only a computer can come up with the right decision. However, the really interesting thing would be which sides messes up less.

Comment: Re:Delivery drones (Score 1) 122

by prefec2 (#49356515) Attached to: How long until our skies are filled with drones?

Our two living zones are obviously very different. I do not see that many delivery vehicle in the streets. And for junk mail. We have a sticker on our letter box stating that no adverts should go in here which works quite perfectly for all kind of leaflets. However, the so called personalized junk gets through. Where I live, we have six parties in the house and most other housed come with at least one additional floor. The letter boxes are indoor to avoid rubbish ending up in them. On the street the wind would pick up everything. I cannot imagine a location where it save to land and save to pick up the letters for humans. However, if that would work in your area. I would be fine with that.

Comment: Re:Easy fix (Score 1) 378

by prefec2 (#49355791) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

You are close, but still missed. Actually, that is also the problem with urinals at large. Furthermore, there are women pilots out there. So if she needs to take a leak the crazy guy at the helm runs the plane in the next mountain. No! The best thing is to use technology which is already there. Option A: Give them diapers, like astronauts. Option B: Give them those in suit urinals which they had on the moon (if I am not mistaken). In both cases no-one has to get up. The latter option could be extended also to a complete toilet which would be important for long distance flights, but you would need a really good ventilation system.


Comment: Re:The girlfriend has some responsibility (Score 1) 378

by prefec2 (#49355719) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

This would look like a guy with low self-esteem which are also easy victims of depression. However, beside what you might have heard on Fox or CNN or read in NYT, that news phase is a guess and a fairy tale. Please wait until the authorities have collected the information and rules out all bla bla which came from the mother of a friend of hers.

Beside that. This looks like you had a similar relationship. In that case, you should go and talk about it professionally. It helps and prevents further situations following the same pattern.

Comment: Re:Pilots must remain in control (Score 2) 378

by prefec2 (#49355617) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

Definitely! We could automate flying, take off and landing, but this would result in other type of incidents. Especially, in extreme situations, humans can think outside of the system, while computers can only reason over the facts they possess and therefore do not have a deeper understanding of reality (this might change in future, but we are not close to that). Beside that, I would not have any trouble going to Cuba, but flying into the side of a mountain is something I would like to avoid).

Comment: Re:Ummmm ... duh? (Score 1) 378

by prefec2 (#49355535) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

No, nothing is 100% save. It is less likely to have two people committing suicide together than one alone. However, this makes it not impossible. If we replace pilots by computers they will go wrong or their communication get hacked or something else, especially, something which we did not think about.

Comment: Re:Parent Post Semantic Content: Null (Score 2) 260

by prefec2 (#49354533) Attached to: How Professional Russian Trolls Operate

No, he/she is pointing out that it is dishonest to throw dirt on the Russians and do like we do no evil. However, if the poster would have read the whole /. teaser he/she would have found the necessary question also at the end of the text. So his/her post is largely redundant. Anyway, it is important to point out that issue and it is also important to point out that the wrong doing of one is not making the thing acceptable for others. Lying is not a nice thing to do (in most cases). The old Jews already knew that thousands of years ago. That's why they had a rule for it.

Comment: Re:Sure (Score 4, Insightful) 260

by prefec2 (#49354475) Attached to: How Professional Russian Trolls Operate

Of course we are saints. We are the good guys. When we deceive the enemy with lies that this is only a tactic to prevent evil. When the Russians do it, it is to undermine freedom and democracy. Welcome back in the eighties, well maybe it is already the sixties. Those old top honchos in the US, UK and the rest of the west have secured another round with Russia with their special inferiority complex based politics. Both sides have hoped to get back to that. For a short time, they thought Islam might be a suitable evil, but that does not work very well when one half of the Muslims tries to kill the other half over things we do not really understand. True, I do not understand why we had that 30 years war in Europe over religion and power.

Comment: Re:But what about flying cars? (Score 1) 122

by prefec2 (#49354263) Attached to: How long until our skies are filled with drones?

Nature is far ahead of us. Flying dogs (Flughunde in German) are already there. In English they are also called flying foxes, but that should be still close enough as a starting point for new dog breeds. They are also infestations of various diseases, just like the original.

Comment: Re:Two answers (Score 1) 122

by prefec2 (#49354153) Attached to: How long until our skies are filled with drones?

Delivery drones only work well in US suburbs. In densely populated areas there is no landing place available near the customer. To become a valid delivery mechanism it must also be better than other options, like delivery to your workplace (home delivery does not work well, because I am not a home when they deliver). Another option would be scheduled delivery in the evening or a common thing in Germany at least, some large yellow box which spits out your parcel when you type in the correct credentials (called Packstation). As these devices are located throughout the city, you can specify one near your normal route home, your home, etc. what ever suits you best. All of this is working much better than a copter can presently and even when considering autonomous flight etc.

Comment: Never will happen (Score 2) 122

by prefec2 (#49354057) Attached to: How long until our skies are filled with drones?

Drones face various problems originating from general avionic and technical/physical limitations, their purpose, material resources, interaction with humans, and energy. Beside all that there are economical strings attached. For example, it might be feasible to deliver packages via copter to the front door of people living in those US suburbs where everyone has a lawn, a car or two, and the roads are wide. However, such living conditions are not the most prominent ones on earth. In Europe people live in much denser populated areas. While there are some areas where you have single houses these areas are small and often mixed in with other housing structures for more than one family sharing the same exit. Even more large parts of European cities are filled with building structures with 4-8 floors with many parties living in the same house or compound. If you visit Beijing or any other Chinese city you can observe that people live in large compounds with 30 or more story buildings. While in Europe you could at least speculate about opening a window, you cannot do that in such buildings. And in China you should not open the window if you are not interested in lung problems. So parcel delivery does not work very well in most areas. It also does not work when I am not at home. However, what works is delivering it to my workplace by humans (drones cannot fly in we cannot open windows).

If you allow copters and humans interact then you have to make sure that there is enough distance between copter and human even for emergency situations. All of this makes parcel copters not to be very likely to become a dominant transportation tool.

Another use case are surveillance copters for police and media. They are already in use. However, they are only then cheaper than non flying cameras when you do not have too many of them.

Each drone requires energy and must be recharged or refueled regularly. All that energy must come from somewhere. If this is more carbon based fuel, we will have increased pollution in cities. We try to get rid of that presently so that will most likely be limited or forbidden. Leaving H2 or electricity (E). H2 requires a lot of energy to be produced and same applies to electricity. However, H2 allow longer flying time while the fuel is more expensive then electricity. Anyway, energy cost is a relevant factor. For a town of 250 000 inhabitants you have 100 roads (densely populated area) with lets say they are layed out like a checkers board (true that does not really fit any town or city in Europe, but who cares). That gives you 104 persons per tile, which would be not enough for where I live, but anyway. Each tile is 200 x 200 m. Making the road length 9800 m. To completely cover the area a drone must fly up and down that approx 10 km. Lets assume that this is done in 20 km/h (median bicycle speed) a complete sweep requires 30 min (29.4). As a typical robbery requires only several minutes, lets say 5, you need 6 drones to get that amount of coverage. That means you need 600 drones and most likely another 600 at the recharger. I do not know what these drones police uses at demonstrations cost, but police equipment is always extra expensive, so 10000 EUR/$ would be an assumable price. 12 000 000 EUR/$ + maintenance + training. Too expensive for the police. Especially, more expensive than just a view officers which could do the same on a bicycle.

Real Users find the one combination of bizarre input values that shuts down the system for days.