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UK Team Claims Breakthrough In Universal Cancer Test

rew Re:So... (63 comments)

They found a statistical relationship between the results from "normal" people and "people with cancer". This means that it MIGHT be possible to develop this into a test.

But this "result" (a statistical difference) might be that they got an average score of 98 +/- 10 for the healty people and 102 +/- 10 for the people-with-cancer. So someone who scores 100, healty or has cancer? 105? Can still go both ways.

about a month and a half ago

Malaysian Passenger Plane Reportedly Shot Down Over Ukraine

rew Number adjusted. (752 comments)

The number of passengers has been adjusted from 280 to 283. There were 15 crew on board.

about a month ago

Are the Hard-to-Exploit Bugs In LZO Compression Algorithm Just Hype?

rew Grain of salt.... (65 comments)

I take such news with a grain of salt. In my experience/estimates, about 80% of security experts report "not possible to reproduce/impossible to exploit" for REAL exploitable bugs.

about 3 months ago

Microsoft Suspending "Patch Tuesday" Emails

rew Re:It looks like a response to anti spam laws (145 comments)

I'm guessing that of the hundreds of thousands of people who get that "mass mailing", some are reporting the mails as SPAM to the authorities. Even if there is an "unsubscribe link" somewhere.

Those that do this, might have subscribed in the past and now no longer use Microsoft software. Or maybe Microsoft at one point decided to add a class-of-users to the list automatically (which I think they shouldn't have done if they did).

In any case, with so many users, the chances of being reported as spammers are 100%. So I understand the pressure to stop.

about 3 months ago

Comcast Converting 50,000 Houston Home Routers Into Public WiFi Hotspots

rew Good thing.... (474 comments)

Here in holland and across europe the same is being done. The thing is, technically, many homes are hooked up with a line physically capable of say 20mpbs, but with only a 10mbps subscription. The extra bandwidth can be alotted to "guest users".

Similarly, even if someone has a 20(or more) mbps subscription on a 20mbps line, he/she won't be using all of it all of the time. So you can again use part of the bandwidth for guests. In this case it would be fair to give the original subscriber priority to use whatever he/she wants, and put the guests at a lower priority.

Oh, security wise they also separate the original subscriber from the guests.

I have the impression they do this "sensibly": the subscribers don't really have a valid reason to be upset about it.

And the thing is: If you're a subscriber, suddenly there are hundreds or thousands of places where you won't be using your 3G datalink but a wifi hotspot. Faster, cheaper!

about 3 months ago

Kids With Operators Manual Alert Bank Officials: "We Hacked Your ATM"

rew Re: Not surprising. (378 comments)

Getting into "admin" mode is a big deal. Even if you don't see a direct way of making money off that, someone else might. (see ingenium's post).

And even then, it should be "confidential information" how much money is in there. If the crooks get to check on the amount that's in there over a period, they can decide to crack it open at "just" the right time. Should improve their "profits" by a factor of two on average.

If you're right and absolutely the only thing they can do is to dispense bills into the "not-dispensed" basket, there is a "denial-of-service" attack: Dispense all bills into the wastebasket just after the machine has been filled. Now the machine will be empty until the next refill. VERY annoying for the people who out-of-habit only go to one ATM.

about 3 months ago

AT&T To Use Phone Geolocation To Prevent Credit Card Fraud

rew Re:Or call your credit card company ... (228 comments)

You have this creditcard. It works in the mall, it works at the cinema. You go somewhere where you know your brother/friend/whatever also has a creditcard that also works in the obvious places. Do you remember to call the credit card company?

What if the bad guys manage to find your account details at a badly protected webshop? They call the creditcard company saying you'll e doing a few purchases across the country (or abroad). Try it once or twice to see what the creditcard company asks to verify it's you, and most likely the crooks will be able to prepare that information.

about 3 months ago

Imparting Malware Resistance With a Randomizing Compiler

rew Are you going to trust a 99% solution? (125 comments)

This doesn't fix the problem. It makes the chances of exploitation a bit smaller, on a "per-try" basis.

Back in the old days, some daemons or setuid programs would do insecure things with /tmp. So the hacker would make a program:
target = "/tmp/somefile";
while (1) {
      unlink (target);
      link ("/etc/passwd", target);
      unlink (target);
      link ("/tmp/myfile", target);
The daemon would check access permissions of the "target", hopefully after the last line in the loop, then open and write the target, hopefully after the second line inside the loop. Leave this running, trigger the target app, and you get the target app to write somewhere where it shouldn't (in this case /etc/passwd. Get it to add "\nmyroot::0:0::::\n" to make the system allow you to login as root without a password....)

The same applies to this stack/compiler randomization tricks: The hacker first tries at a slow pace, but instead of hacking your system, fails to get in because he's crashing your service deamon. You notice your service going down every day or so. Buggy software. Stupid randomization! No time to fix, and you make the daemon restart automatically. And bingo! Now the hacker can try thousands of times!

In cryptography, care has been taken that you can't figure out one of the "bits" of the key by a simple search. So that the exponential search (find the key among 2^256 possible keys) does not become "256 times: find bit n". To guarantee that no "bit leaking" will happen in a buggy program is very, very difficult: The designers of the program don't know where the bug is, the compiler doesn't know where the bug is, but the attacker does!

So... if this goes mainstream, the hackers will find a way to extract little bits of knowledge of the randomization, determine what the actual randomization was, and then attack the service as usual.

Of course, there will be cases where say: the time for the attack is increased beyond the attack-detection-time. So instead of the attack being succesful, the attack might be detected and averted.

Anyway, I much rather have something that actually WORKS instead of "has a chance of working". But maybe that's just me.

about 4 months ago

Gigabyte Brix Projector Combines Mini PC With DLP Projector In a 4.5-Inch Cube

rew Re:My DLP... (44 comments)

As this is from a western company (HP), I expect such technical claims to be reasonably reliable. They claim 1024x768 resolution, which is 100% correct. For something less easy to measure (for me), if they claim 2000 ANSI-lumen, I expect at least say 1800, with the "excuse" something like: we put it on the "boost" setting for that measurement (and then decided not to put it in the final product because it reduces lamp-life a lot).

about 4 months ago

Gigabyte Brix Projector Combines Mini PC With DLP Projector In a 4.5-Inch Cube

rew My DLP... (44 comments)

I decided 15 years ago when I bought my DLP projector that I wouldn't settle for less than 2000 Lumen. Back then this was an expensive "restriction". But 75????

about 4 months ago

Tux3 File System Could Finally Make It Into the Mainline Linux Kernel

rew Re:Ready for mainline? (121 comments)

Daniel phillips, where have I heard that name before? It was in the last few days.... :-) Ah! :-)

about 4 months ago

Tux3 File System Could Finally Make It Into the Mainline Linux Kernel

rew Ready for mainline? (121 comments)

To be taken serously, the home page needs to mention something more recent than 2008 in the "on the web" section. And the "we're active, see the git log" link needs to point somewhere other than a 404....

about 4 months ago

Ask Slashdot: Preparing For Windows XP EOL?

rew Re:No problem (423 comments)

Haha. I worked on a project where the machine doesn't const a lowly $50K. The machine costs on the order of $2M. The machine has processed (I just looked it up) about $40B worth of product... And it's still running software from around '2000. (installed in '97, upgraded in '00)

about 6 months ago

Ask Slashdot: Preparing For Windows XP EOL?

rew Re:No problem (423 comments)

I wrote software that is now cloned to 5 machines. The machine runs a terribly old OS, no longer supported. But the rest of the machine cost about $2M each....replacing them or part is not an option! So: don't connect it to the internet. These machines have processed countless billions worth of product. The product is worth more than whatever can be found on the machine, so yes the operators will be able to use a privilege escalation bug to gain root access.

Anyway, they run Linux 2.4 on Suse 7.2....

about 6 months ago

Why Birds Fly In a V Formation

rew Re:This is new? (207 comments)

Same here.

about 8 months ago

Website Checkout Glitches: Two Very Different Corporate Responses

rew Re:Same rules apply (303 comments)

> Yes.... but I belive that's more about HONORING What you advertise.
> If the printed price they stuck on the goods says "$300" on a $3000 on
> a brand new Macbook pro; they better honor it.
In The Netherlands, the law states that they have to honour the advertized price as long as it can be reasonably assumed not to be an error. With mega-discounts and super-cheap deals for various products the "spot the error" can become difficult. On the other hand, the $300 on the $3000 macbook would be considered an "obvious error".
The $80 for a $800 flight however cannot! The cheap airlines have been selling fights for that kind of rates for ages, so even when an airline that normally doens't do this proposes such a deal, that should be considered "entirely plausible" by the consumer.

about 8 months ago

25,000-Drive Study Gives Insight On How Long Hard Drives Actually Last

rew Bad statistics. (277 comments)

The "bends" in the curve they plot are too abrupt. There must be something else going on.

Looking at the original article, they had only about 3500 drives around 2009. That's 4 years ago. So their "4 year" survival rate is not based on the 25000 drives they have now, but only on the 3500 that they had in 2009. With the sharp bends in the curves around 1.5 years and 3 years, I think they significantly changed their buying policy around those moments. Or the manufacturers started shipping them different drives.

How else can the drive "know" that it's been on for 1.5 years? The annual failure rate drops by a factor of four inside a month.

The explanation of the bathtub curve eplains it a bit, the random failures is apparently about 1.4% per year. The initial failure is about 5.1-1.4= 3.7 per year. But instead of the initial failures "tapering off" to "small" values around 1.5 years, they stay constant for 1.5 years, and then suddenly drop to zero. To me this points to something like: "they bought a big batch of drives about 1.5 years ago that has such a high random-failure-rate to pull the average first-1.5-year average up to 5.1%/year".

Do the same analysis 3 months from now, and the "1.5 year bend" moves over to 1.75 years. That's my hypothesis based on the data they publish. Having the underlying data and some time to spare, the current data may debunk or prove my hypothesis already. (e.g. if you run the analysis on the data that is now older than 3 months will, if my hypothesis is correct, show the bend around 1.25 years. If that happens, it makes my hypothesis very likely.....)

about 10 months ago

GPUs Keep Getting Faster, But Your Eyes Can't Tell

rew Re:You don't need a GPU. (291 comments)

What I'm trying to say is: In theory a CPU is fast enough to refresh all pixels within the time of a single frame.

But having a GPU that can do things to the screen while the CPU does other neccessary stuff makes sense. It starts with 2D bitblits.

about 10 months ago

GPUs Keep Getting Faster, But Your Eyes Can't Tell

rew You don't need a GPU. (291 comments)

You don't need a GPU at all. A screen is 2Mpixels. Refreshing that about 60 times per second is enough to create the illusion of fluid motion for most humans. So that's only 120Mpixels per second. Any modern CPU can do that!

Why do you have a GPU? Because it's not enough to just refresh the pixels. You need (for some applications, e.g. gaming) complex 3D calculations to determine which pixels go where. And in complex scenes, it is not known in advance what objects will be visible and which ones (or part) will be obscured by other objecs. So instead of doing the complex calculations to determine what part of what object is visible, it has been shown to be faster to just draw all objects, but to check on drawing each pixel which object is closer, the already drawn object or the currently being drawn object.

about a year ago

How Safe Is Cycling?

rew Re:How safe? (947 comments)

In Holland, 100% of the car-cyclist collisions are "caused" by the car. The law was modified to DEFINE it that way. The motorist is ALWAYS responsible.

On the other hand, "poor decisions by the cyclist" is still compatible with: "caused by the motorist". If the cyclist takes more "margin" a traffic violation (would've "caused" the accident) by a motorist will avoid injury.

One of the things I always do while cycling is: if they don't CLEARLY give me the right-of-way that I have, I slow down so that I can stop in time for them without getting hurt. This will COST them time. Because I can't speed up infinitely fast once they HAVE clearly stoped for me (and I might pretend to be speeding up quickly afterwards, while in fact... not.. :-) . If 10-20% of the cyclists do this, the motorists will learn to properly respect the right-of-way rules soon enough....

about a year ago



text based matching software.

rew rew writes  |  more than 2 years ago

rew writes "I run a small company. I get invoices for the stuff that I buy to run the company. These are scanned, OCRed and then need to be filed in the invoices system. This last step I've tried to automate, but it doesn't work very well. So my question is: Does anybody know any (open source) software that would help me automate this?
The biggest problem is: the OCR software sometimes gets things slightly wrong. What I have triggers on keywords. But an OCR-error in the keyword will throw things off completely. As a human I can see hundreds of other hints that for example this invoice comes from that company. I'm thinking some bayes statistics and/or neural networks should be pretty good. And my database of manually handled invoices should provide a good training set. But the bayes software that I found works for one parameter: spam/notspam. And not for things like: "amount: $123.45". Similarly I don't think that neural networks are able to output that "amount $123.45" that is needed in this application. Here the hints should be things like: "the amount will be on the line following....." and "the amount is preceded by ...."."


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