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Comment Beyond Rockets (Score 1) 101

Maybe before Musks thinks about how to get stuff to Mars he could solve the problem of better (especially with less energy use) getting stuff into space. At about $10000/kg for Earth orbit there will be no way a Mars station will be resupplied for long.

So we need a space elevator or some mag-lev "cannon" (preferably on the Moon to avoid the air friction) before we can go seriously out to explore space using humans. Rockets are like steam locomotives (actually they are worse) they carry all their propulsion needs with them in a quite inefficient way.

Comment Re: Take back Slashdot (Score 2) 1305

And maybe we (yes, we!) can cut back on uselessly exagerated, ridiculing strawmen to derise a non-agreed opinion. Just because other people's posts seem to be completely stupid doesn't mean they require hateful responses. One could just ignore them.
I at least promise to do so. As a new year's eve resolution. Of next year.

Why did I post this? Because although I remember some news stories on women in tech (which I might have agreed with or not), I can't remember any story implying "everyone in your industry are chauvenists assholes and you owe us a place in your ranks". Let's stay at the facts.

Comment Re:Take back Slashdot (Score 1) 1305

- Allow older accounts who have good standing being able to post faster. The 4 minute time-out is archaic compared to reddit

Write comments thoughtful enough to take longer than 4 minutes to write. Like this ;-)

TL;DR: We have enough "I wish I had mod points" and other one-liners. No need to add a mechanisms to get more of them even if you think you would never use it that way.

Comment Re: The "Floor" was always a kludge (Score 1) 138

Of course, people use past information for predicting the future, how is that in any way remarkable, or a problem?

Uhm, because if the market really was evaluating the price of a commodity (including all the information about the future), then the history of the price only tells you about how humans previously evaluated that information. That is great if one wants to exploit human psychology (or nowadays machine psychology in terms of having better algorithms than the neighbouring bank). But then the AC's statement of the market price not expressing current value but including expected future speculation (at least that's how I interpret it) is true.

Obviously, if you trade ten times as fast, your market moves ten times as fast. But you claimed that the swings don't just get faster, they also get bigger in magnitude than they would for a slower moving market.

Yes, I claim it because during those few minutes, seconds, milliseconds of machine trading the only information which changes is the (recently) past price, thus there is no other influence on the set-point than what is itself based on that influence.
In contrast in a theoretical very slow market (lets say 3 trade points a day) other - more real world (aka fundamental) - information has time to influence the set point before a trend can even be recognized and followed. So new news (the previously announced contract will be delayed, the government decided to spend more money due to the castastrophic economic predictions of yesterweek) or new insights (careful analysis of the announced contract shows low ROI in comparison to similar contracts, the economist making the predicitons have bad track record of correctness) can stop trends early.
Obviously such additional information could also strenghten trends. But then the price would really be a "prediction" of future value (as far as that is possible) based on new information and not just - exaggerating - the extrapolation of the step function response of the market to the last information. Does not prevent bubbles as history teaches us (human psychology again). But those take years and not merrily hours, so the (financial) environment has time to adapt.

Comment Re: The "Floor" was always a kludge (Score 1) 138

Unfortunately, "market" price does not mean what it sounds like (ie, the value of something _right now_); it includes future speculation.

Predictions about future returns are part of "the value of something right now", so your distinction makes no sense.

I think what would be better to say is that market price itself is used as information for future speculation.

In fact, the opposite is true mathematically: longer delays tend to produce bigger swings, for the simple reason that a system can go off the rails longer before the market corrects it.

It would be true for a "real" control system, i.e. a system which tries to control a variable to achieve/follow a setpoint. In such a system the shorter the delay the better the variable will follow the setpoint. Yet due to technical analysis (i.e. trying to predict the future price of a commodity from the "chart" of the price up to now) in financial trading the variable can influence the setpoint. In such a scenario a short delay can mean sharp, large swings. So instead of a depression of prices over months they will fall within an hour. Or rather would fall if there hadn't been circuit breakers installed on automated trades. So if automated HFT was so great, why does the NYSE limit it when it looks to start running amok?

But there's an even more basic error in your reasoning, namely the assumption that market swings are bad or that we should adopt policies to reduce them.

Comment Re:Would make sense for a military base. (Score 1) 101

As the article you cite shows, the U.S. had as least the pretext trying to prevent an accident by an already de-orbiting satellite and the remains of the destruction de-orbited within a few months.

Now of course the U.S. could just have had its satellite de-orbit on purpose but even then this launch could be seen as a demonstration of U.S. capabilities necessary after the Chinese test to uphold mutual deterence ("If you kill our satellites, we will kill yours").

Comment Iran a democracy? (Score 3, Insightful) 229

Uhm, it is a 'democracy' where eligibility is limited by a religious council, ultimate power is held by a not-popular-elected (not even indirectly) individual with potentially dictatorial authority, suspicion of massive voting fraud exists, where independent polling organisations are closed down to hide this, and where the press is severely limited ("one of the world’s most repressive in 2014" ; Last but 7 in 2015).

Please remember: "Voting not a democracy make."

Comment Re:What else is searched for (Score 2, Informative) 284

Yes, just imagine an alternate relaity in which Donald Trump becomes president, enforces his "Scare the Muslims away" policy by requiring them to wear clearly visible marks on their clothing and the document being a call for civil disobedience telling among other things how to produce markers which look OK but will not be visible for automatic surveillance cameras.
Obviously everyone forwarding such a document is not a law-abiding citizen but a prospective terrorist and needs to be found and detained.

Comment No need to crack the camera (Score 1) 77

There is currently a report by a German computer magazine (no so good Google translation) where IP cameras sold by a large German supermarket chain had an awfull standard configuration in
a) Not asking for a new password for external access and
b) automatically opening (via UPnP) an existing firewall.
Seemingly even after an update there are still hundreds of these cameras reachable on-line.

So one does not have to wait for a malign party to 'crack' a camera. Insufficient security knowledge at manufacturer and user is enough.

Comment Legal situation? (Score 1) 720

I also wonder about the legal situation of manipulating registry entries to circumvent user decisions. There are a few laws in Germany which as if they could fit (but IANAL):
303a Data Manipulation
(1) Anyone who illegally deletes, supresses, renders unusable oder changes data shall be punished with imprisonment of up to 2 years or a monetary penalty

303b Computer Sabotage
(1) Anyone who significantly disturbs a data processing [process], which is of significant importance to someone else, by
* an act according to 303a
* injecting, entering or submitting data with the intention to create a disadvantage to someone else, or
* destroying, damaging, rendering unsuable or changing a data processing system or data storage medium
shall be punished with imprisonment of up to 3 years or a monetary penalty
(2) In case the data processing [process] is of significant importance for a (different) business, company, or a civil administration the punishment shall be imprisonment of up to 5 years or a monetary penalty.
(4) In especially serious cases of section (2) the punishment shall be imprisonment of no less than 6 month to 10 years. As a rule a specially serious case is if the culprit
2) acted businesslike or as member of a gang which formed for continuous perpetration of computer sabotage.

And according to 202c distributing computer software which is intended to commits such crimes is punishable, too.
[all my translation; definitely not authorative]

So now the questions are:
* Was the manipulation of the registry values illegal?
* Was a company or civil authority hit? (Note that the law does not say "Void if they should have set up a Domain")
* Is Microsoft's approach "businesslike"?
Because if all is answered yes, then anyone involved in programming and distributing GWX.exe should better avoid Germany for some time to come (I don't know the statue of limitation on this).

Comment Re:Summary wrong, not secure (Score 3, Informative) 19

No, the first attack assumes the identity provider to use an 307 request in answering a valid used identification request from the malicious server (which might look to the outside as a normal service while secretly retrieving user password). As far as I understand the forward will always happen in the protocol. The assumption is that this is done with a 307 request instead of 302 (or 303). This was apparently allowed by the OAuth specification (although one can of course wonder why any ID provider would not use 302 or 303).

Reading the original paper (and not just the blog) really helps to understand the attacks. With respect to the second attack I immediately thought that it wasn't worse than any authentication not using HTTPS. But the authors point out that they attack a step of the protocol (selection of ID provider) not normally considered sensitive so it could happen in HTTP.

Comment Authors maybe know what they are talking about (Score 1) 100

Well. I think the authors do have some points although at least some of them are existing in embedded systems (which execute directly out of Flash) for a long time:
* CPU cycle hungry, most efficient disk caching algorithms are not that efficient anymore once "disk" (or rather Flash) access manages to catch up to the CPU. Less efficient but also less resource hungry algorithms might be advantageous then.
* Issuing lots of read accesses in advance to keep your worker threads busy might only help in occupying RAM but not speed up processing anymore if data arrives long before workers finished their previous job.
* Multi-core access to the Flash needs better (and less blocking) synchronization than with disk, where actual colliding accesses would have been more rare due to long time between them (being executed).
* If serial and random accesses show only small difference in access times (as they do for Flash: a few clock cycles for the Flash to throw away its read-ahead cache and get new data instead of the huge wait for head positioning and sector arrival of spinning disks), caching strategies might have to change, e.g. maybe caching leaf inodes is then not efficient anymore (just guessing here).
* And they seem to be talking about networking due to attaching disk clusters to servers via ethernet. But there I guess the authors are not radical enough: Why not connect the Flash devices directly to the server, they take much less space and power than spinning disks.

But as I said, I would have expected many of this being explored with respect to embedded computing long ago and with respect to servers already since the advent of the first SSDs (by talking to the embedded guys). Now seems a bit late for an ACM magazine article about that (unless ACM is falling behind tech development).

Comment Monopolization of on-line services (Score 1) 460

Once Uber has driven its competition out of business, anyone will be able to offer a service like Uber, because the barriers to entry will have been removed.

Yes, that is exactly what we see in other comercial areas such as
* On-line Book selling (uh I meant selling of nearly everything)
* On-line auctions
* Search engines (uh I meant news integrator, mobile OS vendor, and whatever else)
* Social networks
In all these areas, after the first guy opened the market we see the business spread evenly over more and more companies with none coming near a monopoly which it could potentially abuse to e.g. make experiments on its users.

Comment Re:Alternate Title (Score 1) 179

I stopped reading after he claimed "Hard to be a god" was a call for "good" science (whatever good means in this context) when it is (at least in my opinion) nearly the opposite: A tale that even the best intentions do not guarantee favorable outcomes and that even scientist are not save from believing otherwise until their intentions fail.
So I take the rest of the article was similarly messed up?

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