Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror

Comment: Re:This is a ridiculous way to make concrete. (Score 2) 94

by j-beda (#49698695) Attached to: Biologists Create Self-Healing Concrete

My concern is, if this stuff works, how much will it work? Will it repair itself in the same area more than once? What is to stop the bacteria from forming a big lump on the surface after they bridge the crack's gap. Is the replacement material even nearly as strong as the original concrete or will it just break again under less stress? If the intended use of this for building construction or surfaces to walk on? I can see it being used in 1-3 story buildings as material, but any where solid concrete has to be used instead of those hollow cinder blocks, I can't see it being possible, much less if water is needed to activate it.

Being able to repair small cracks to keep water out would go a long way to minimize the freeze/thaw damage that makes small cracks into big cracks. Even without the same strength as uncracked concrete, concrete with some small filled cracks will perform much better and last much longer than concrete with growing numbers of growing sized cracks.

Comment: Re:that's fine (Score 1) 408

Honestly, you can say it wasn't their fault, but nearly 10% of them in 6 months have been involved in accidents. Even if it wasn't the fault of the technology itself, why is the accident rate so high?

One does need to factor in the number of hours/distance driven. I would not be too suprised if their per mile or per hour accident rate was much lower than the average. Of course, small numbers of vehicles will tend to give larger variance - this 6 month period might just be a statistical outlyer.

Comment: Re:US South (Score 1) 187

by j-beda (#49658475) Attached to: Interactive Map Exposes the World's Most Murderous Places

So much for theory of gun states having less crime.

When I looked at the estimated per-capita gun ownership rates by state, and the per-capita homicide rates per state, I didn't find a clear correlation.

Interestingly, it does appear that states with a higher gun homicide rates also have a correlation with higher non-gun homicide rates.

I think that there is a pretty strong correlation between a "culture of honor" and interpersonal violence. The social norms that insist on retribution and payback for transgressions, outside the pervue of established law inforcement can also contribute.

https://en.wikipedia.org/wiki/...

Comment: Re:The cause DOESN'T MATTER (Score 1) 187

by j-beda (#49658429) Attached to: Interactive Map Exposes the World's Most Murderous Places

If I see a Black Person, I see someone that belongs to a group statistically way, way more likely to murder or injure me. They are more likely to do drugs, be poorly educated and be a deadbeat father.

It simply doesn't matter what the root cause was, I know they should be avoided.

If you were interested in designing and/or implementing public policies to reduce crime, drug abuse, etc, then understanding the root causes is probably pretty important. If your only interest is in minimizing your personal exposure to risk, then understanding the actual statisctical underpinings of your fears might also be of use. Is your actual risk actually changed if you avoid ALL blacks? Should you be looking at relative risk changes or absolute risk changes? Are the risks worth worrying about in any case given your current risk parctices in terms of driving, eating, smoking or other potentially dangerous activits. Worring about 5 murders per 100,000 population might not be as important to worry about when you compare it to more than twice that rate in automobile deaths for example.

https://en.wikipedia.org/wiki/...

Comment: Re:I'll save you 30 seconds of Googling (Score 2) 257

Phi Sigma Sigma secrets are:

Phi Sigma Sigma (PSS) secretly stands for Philanthropic Social Society. However, this is never written down or recorded (until now) because it is so "sacred". The Handshake consists of a series of motions. Member A first begins ....

Assuming that you can find the poster, and that the poster is in fact a PSS member who might possibly have some sort of obligation to keep the secrets, how would the complainants ever hope to establish that these were the actual secrets if they have never been documented? Wouldn't they need to have testomony from the people who shared the rituals with "Jane Doe", and wouldn't that testomony have to go into the public record during the trial?

I suppose the judge might order the trail records sealed like is sometimes done when a vunerable minor dis involved with the courts, but it doesn't seem likely the courts would care much about such things in this type of case. Is there a "Greek Friendly" court in Washington somewhere like the "patent friendly" on in Texas?

John Oliver bit on patents: https://www.youtube.com/watch?...

Comment: Re:Hooray for druggies! (Score 1) 409

The dogs are consistently abused

Please cite some actual examples of police dogs being constantly abused. You have no idea what you're talking about.

I think "The doges are used in away to abuse the 'suspects'." was closer to what was meant, rather than that the dogs were being mistreated. There are numerous studdies to suggest that the potential for abuse exists:

http://nevergetbusted.com/neve...
http://www.informationliberati...
http://www.wayne-county-forfei...

Comment: Re:Hooray for druggies! (Score 1) 409

Or they can be trained to alert on whatever signal their handler wants to give them. Hell, they are dogs, they want to please their handler.

That sentence was valid with "their": "Hell, the handlers dogs, they want to please their handler."

" handler's ", or perhaps " handlers' " but that is less likely as the final "handler" is not plural.

Comment: Re:Decent (Score 1) 482

by j-beda (#49487727) Attached to: Seattle CEO Cuts $1 Million Salary To $70K, Raises Employee Salaries

If he is married, $70,000 puts him in a federal tax bracket where his long-term capital gains rate becomes 0%. He is doing this to pay 0% taxes on his stock that he cashes out and any other investments he has.

Really? A quick look at Wikipedia seems to support your statement, but surely this type of obvious loophole is easily plugged by putting some minimums or maximums into the tax code.

https://en.wikipedia.org/wiki/...

Can I really gather in all of my cap gains tax free by just making sure that year I have a low enough salaried income? So every decade or so I get my employeer to give me a $1 salary and make sure that in that year I liquidate all of my holdings and then reinvest them, and have thus avoided any tax on my millions of Cap Gains?

Of course, I actually do not have millions in unrealized gains to take advantage of this type of thing...

Comment: Re:Fine theoretical work but.... (Score 1) 136

by j-beda (#49478799) Attached to: Cracking Passwords With Statistics

...how many systems let you try new passwords ad-infinitum, rapidly? I know back when I was in college I could brute force Windows shared folders (script kiddie style), but nowadays I'd expect any semi-serious authentication system to limit the number and frequency of login attempts.

I am not an IT professional engaging in rhetoric; I'm actually curious.

No online system is fast enough to brute force an account even if they did allow you to try new passwords ad-infinitum - each attempt would take a second or two and that's just too slow for effective "cracking" I would think.

I believe that the concern is for when there has been a data breach of some sort, and the "bad guys" have gotten the username/password file. The data in this file has been run through some sort of a one way function and thus you cannot just read the usernames and passwords out of it, but since the attacker knows what the one-way function is, they can test to see if any username or password that they want to know about is in the file, and they can do this with all the computing power at their disposal. "Rainbow" tables are pre-calculated results of this one-way function for common usernames and passwords.

The data in the file can be "salted" adding an extra bit of information to the password before running it through the one-way function - even if the "salt" is known by the attacker, this prevents rainbow tables from being useful. There are probably also ways of combining unique salt values, usernames, and passwords so that even "insecure" passwords are difficult to recover from the file, but of course the longest passwords drawn from the largest possible set of characters will always be hardest to "crack".

Comment: Re:I've seen the prior-art Swiss watch (Score 1) 111

by j-beda (#49419921) Attached to: Swiss Launch of Apple Watch Hit By Patent Issue

Although the Girard-Perregaux Complication Bombastique Impériale was a marvel of its time, the complex geartrains required to write and mail letters, answer telephone calls and listen to the wearer's heartbeat was impossible to keep repaired and lubricated in the field, besides resulting in a device too heavy for any real-world wrist to carry. Though the concept watch was a hit at the Basel trade fair that year, the very idea of having to use a tiny set of platinum screwdrivers to connect the device to a cash register to use the payment feature was a major impediment to sales.

Just another failure of the market.

Comment: Re:Clearly the ARTICLE's a scam (Score 1) 349

by j-beda (#49376353) Attached to: Sign Up At irs.gov Before Crooks Do It For You

Actually, it's impossible to file without W2s.
So, yeah a crook might be able to glem stuff,
they can't file for you.

It looks like if you (the crook) sign up you can view your victim's old W2s, and from them you can fake it for the following (current) year, fill out a tax return based on those faked W2s and get the refund sent to a compromised bank account. Withdraw the refund money and run away.

Comment: Re: Be careful what you ask for (Score 2) 349

by j-beda (#49376239) Attached to: Sign Up At irs.gov Before Crooks Do It For You

What, they don't use more gas / pay more gas tax than the rest of us?

Not in proportion to the wear on the roadway they produce. I think the roadway wear goes as either the square or the cube of the weight per axle, and the big trucks weigh a lot more per axle. Nope - looks like it is a fourth power relationship:

"Road damage rises steeply with axle weight, and is estimated "as a rule of thumb... for reasonably strong pavement surfaces" to be proportional to the fourth power of the axle weight."

https://en.wikipedia.org/wiki/...

It looks like the max axle weight is something like 20,000 lbs. while the average passanger vehicle weighs something like 3500lbs, which would be under 2000 lbs per axle. Thus each very heavy truck can be even more than ten times the axle weight of the average car - and 10^4 is 10,000, so that truck can cause as much wear as 10,000 cars. Or maybe that 10,000 factor is per axle (five axles in an "18 wheeler"), so maybe it is a factor of 25,000 when comparing an 18-wheeler to a car.

Wow - trucks really tear up the roads!

Comment: Re:Too much manual formatting compared to LilyPond (Score 1) 35

by j-beda (#49336219) Attached to: MuseScore 2.0 Released

The automatic formatting of LilyPond is much better. The workflow is similar to TeX: you write content in a text format and mark it up, and the software takes care of the rest. The quality LilyPond can achieve is very good. With MuseScore, though the visual interface is more comfortable for many and has a smaller learning curve, there's far too much manual adjustment necessary in scores of reasonable complexity, and usually has to be done again when a piece is modified. It's possible to get the best of both though, by importing a MuseScore into Denemo, which uses LilyPond for typesetting. Some examples here show the difference, compared to using MuseScore alone.

I'm glad that it sounds like there is a way using denemo to go from MuseScore to LilyPond. Is there a way to go the other direction? Having the scores in a format with easy portability and long term viability seems very important.

Comment: Re:How fucking tasteless (Score 1) 341

by j-beda (#49335953) Attached to: Feds Attempt To Censor Parts of a New Book About the Hydrogen Bomb

Except facts and history do not agree with you.

Fact is that Japan offered to surrender BEFORE the bombs were dropped. They had one condition, that their emperor would not be harmed. The US required unconditional surrender.

The US wanted to a) test the effects of radiation on humans (primarily civilian targets were chosen), and b) the US wanted to drop the bombs as a demonstration to (their allay), the Soviet Union.

Not a position piece, but plenty in there to support the above assertions:

http://nsarchive.gwu.edu/NSAEB...

I did not know about the offer to surrender with conditions. I do not see a lot of evidence for (a) being a significant factor, but can certainly believe that (b) was a consideration.

Comment: make it light (Score 1) 385

by j-beda (#49290695) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

Probably nobody will read this since it is way down at the bottom, but in my opinion the best choice would be something very light and portable.

In her chosen field, all of the really heavy lifting will be done on external clusters or the like - so something that can open a secure shell on a remote system and transfer files easily is the only thing that is really neccessary. Larger and larger portions of the scientists I see and/or support are purchasing MacBook Airs because dragging a tiny 11" model around all the time is way easier than anything larger. Then plutting it into a monitor and keyboard when at the desk, and you're good to connect to the server doing the real work.

As much as I like the Macs, there are probably reasonable other ultra-portables that are worth considering if the Windows or Linux environment floats your boat, but the Mac does fit with lots of hardware and software.

Some of my readers ask me what a "Serial Port" is. The answer is: I don't know. Is it some kind of wine you have with breakfast?

Working...