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Comment: Re:"Free" exercise (Score 1) 284

by Macman408 (#49125343) Attached to: I ride a bike ...

That description basically sounds like the San Francisco Bay area to me...

If you're interested in riding, find someone else who does it, and they may have helpful tips on where to ride. As you get more experienced, you might find yourself more comfortable sharing the road with cars - but certainly initially, most people prefer to take quiet residential streets or sidewalks. (Personally, I think sidewalks are a terrible idea for bikes - nobody is looking for you, and there are lots of driveways and obstacles. But if that's the only way that people feel safe riding, so be it.)

Comment: Re:Changes based on the Season (Score 1) 284

by Macman408 (#49125305) Attached to: I ride a bike ...

I used to ride a hybrid in the snow with nearly-bald medium-width tires (28-32 or so, I moved narrower over several years). I usually avoided the 8-mile commute when it was actually snowing and cars were sliding around everywhere, though. Only fell twice on those skinny tires; both were when I tried to make ~90 turns at low speed. At higher speeds, the bike still wants to stay upright, even if there's no traction.

Layers are good, but nothing helps when the temperature is negative (F) and you start breathing hard when you go up a steep hill... I could feel my alveoli freezing with every breath. Never stopped me, though...

Comment: Re:"Free" exercise (Score 1) 284

by Macman408 (#49125279) Attached to: I ride a bike ...

Yes. There's a group of people that rides from San Francisco to Google in Mountain View; roughly, it's 42.5 miles, though it's a bit different for each person, because most riders: 1. don't live at the coffee shop(s) where they meet up to start the ride, and 2. don't necessarily work at Google. Once they get to Google, smaller groups branch off in the directions of all the other area tech companies.

Just from hearsay, though; I've never ridden it myself (my commute is a bit tamer), though I've considered trying their route out for fun sometime.

In case the 42.5-mile ride is not to your liking, there are alternate scenic routes that go 48 or 62 miles, at a cost of more hills.

Comment: Re:Sheesh! I thought Reiser had a bad defense... (Score 1) 73

As a follow up, I saw something today after the verdict was announced that quoted his attorney; apparently the pre-trial negotiations didn't offer anything meaningful in terms of a reduced sentence if he were to plead guilty, so they didn't take it.

Comment: Re:Terrible lawyering by the defense (Score 1) 257

by Macman408 (#48985241) Attached to: Ross Ulbricht Found Guilty On All 7 Counts In Silk Road Trial

I found this Ars article rather illuminating:
http://arstechnica.com/tech-po...
Specifically, this quote at the end:

Ulbricht received a fair trial. The judge was hard on the defense, but that is largely due to how the defense acted and their strange tactical decisions.

In one of the judge's orders (I believe the one excluding his expert witnesses), the Judge blasted the defense as having made a calculated risk - they didn't want to show their hand so that the prosecution couldn't show evidence to counter the defense strategy, so they waited until the last minute to add their experts to the trial. However, the prosecution saw some of this coming and dropped a ton of evidence on the jury - and the judge saw through the defense's strategy and ruled against them:

If defense counsel truly planned his trial strategy around his ability to bend the rules and examine witnesses outside of the scope of their direct, then he should have had a “Plan B” that included complying with the rules. Defense counsel took a calculated risk.

I'm sure that this will get stuck in appeals for quite a long time. The best thing the defense can do in a situation like this where all the evidence points to guilt is to try and stir up confusion by throwing everything at the wall, and waiting to see what sticks. They only have to get lucky once to get a "not guilty" that will forever absolve Ulbricht, thanks to protection from double jeopardy.

Comment: Re:Sheesh! I thought Reiser had a bad defense... (Score 2, Interesting) 73

They might not have offered him a deal, or he might've been too stupid to take it. The prosecution apparently accused him of thinking he's too smart to be convicted (speaking of Hans Reiser...), and Ars Technica had an Op-Ed speculating that he might not be taking the advice of his lawyer as much as he should be - or his lawyer isn't doing a good job.

Reading Ars Technica's great day-by-day coverage of the trial, I think the prosecution has probably done a great job of tying up all the evidence in a beautiful package for the jury, while the defense laid out a haphazard tale meant to distract and confuse the jury. This is exactly what happened when I served on a jury a couple years ago - maybe 3 of the people on the jury were somewhat swayed by the defense's arguments, but after a little deliberation, the rest of us convinced those 3 that he was guilty beyond a reasonable doubt.

I think the defense attorney probably did his job here in trying to confuse things - but seeing how the evidence was presented in Ars's articles, I think that he'd have to get really lucky with the jury to get an acquittal at this point.

Comment: Re:Malicious code can cause computers to crash (Score 1) 138

by Macman408 (#48669711) Attached to: Many DDR3 Modules Vulnerable To Bit Rot By a Simple Program

It depends a bit on the physical structure of the RAM, but for the most part, the errors fall on logically adjacent rows (i.e. nearby memory addresses) in the RAM. So most of the time, you'll only affect other RAM inside your sandbox, and if you affect something outside the sandbox, it won't be far outside.

I remember encountering a similar failure when designing a system; the particular memory controller and the particular DRAM module we were using both met all applicable specs, but when used together in a particular manner, they would fail miserably. The specific test was to alternate writing all zeros and all ones at different addresses. The RAM controller had an oddity where it would enable the drivers for the RAM data pins a very briefly before the data was known. For that particular data pattern, that meant that it would drive all ones on the data pins to the RAM for less than a nanosecond, before starting to drive all zeros (or the reverse). There's nothing really against that in the spec; the data was all correct for all the relevant setup and hold time requirements relative to the control signals. However, it caused a lot of noise on the ground plane of the DRAM module; we measured as much as 0.75V or so. (That's measuring the ground voltage on one side of the SO-DIMM to the ground voltage on the other side; it's shorted by a mostly-solid layer of copper, but that just wasn't enough to carry all the current with this particular access pattern.) So from the point of view of the RAM chips, it's a little like having your 2.5V supply voltage suddenly drop to 1.75V. It messes up all the reference voltages, so a 1 might be interpreted as a 0, or vice versa. The memory controller manufacturer refused to do anything about it (and it would've taken them many months to redesign and respin the chip anyway), but the RAM module manufacturer was friendly to us, and they beefed up the ground plane so that the noise level was much more manageable.

In any case, I'm sure there are thousands of faults like this that are just waiting to be found and exercised in any given system. No modern computer is 100% tested, they're far too complicated. There will always be some weird sequence of things that could happen and trigger some failure - but hopefully that sequence is so odd, it'll never happen.

Comment: Re:Not seeing the issue here (Score 2) 209

by Macman408 (#48650507) Attached to: Judge: It's OK For Cops To Create Fake Instagram Accounts

Negative. When I served on a jury, the judge *specifically* instructed us that we were not to lend any more credence to the testimony of a police officer than to any other person, solely because he/she was an officer. During jury selection, anybody who either would never trust a cop *or* would *always* trust a cop was dismissed.

That said, we trusted the cops anyway, because their story made a lot more sense than the guy and his wife saying "nuh-uh, that meth wasn't mine, bro," with no other evidence or witnesses to prove it. Meanwhile, the police presented evidence such as the meth pipe, the letters addressed to him that the pipe was sitting on top of in his bedside table, the meth that was in it, and a record from his roommate/alleged dealer/meth cook that he was indebted (the presumption being that it was for meth).

I won't disagree that they are probably trusted by a jury more often than other witnesses for a variety of reasons (a lack of obvious motivation to lie, an appearance of professionalism, a calm demeanor under pressure, etc.), but the court itself does not hold them up as model witnesses.

Comment: Re:I'm shocked. (Score 1) 191

by Macman408 (#48614469) Attached to: Apple Wins iTunes DRM Case

I was on a jury recently (for someone accused of misdemeanor possession of methamphetamines). Some of the questions that the judge asked every potential juror were exactly along this line:
- Do you actively participate with any groups that advocate for or against the legalization of drugs?
- Do you believe that possession of a small amount of drugs should be legal?
- (If either of the above was true:) Will you follow my instructions regarding the law, even if it disagrees with your beliefs?

Anybody that wasn't willing to follow the judge's directions was excused from service.

Of course, that also meant that a surprisingly large fraction of the people in the jury room claimed that they either used meth themselves, wouldn't convict someone of meth possession, or had a close family member or friend that used it; and that they wouldn't follow the judge's instructions on the law - they all knew they would be immediately excused and not have to show up for the rest of the week.

I told the truth, and ended up on the jury. It was an interesting process... Plus I got $68.16 to compensate me for my week's worth of time!

Comment: Re:UPS (Score 1) 236

by Macman408 (#48438209) Attached to: What is your computer most often plugged into?

I honestly don't know how much it applies to desktops, but certainly in other form factors, you can't rely on TDP as an indicator of the size of power supply needed. TDP tells you how much heat the heatsink needs to be able to dissipate. If you exceed the TDP for a few seconds, there's enough thermal mass that you won't exceed the maximum junction temperature of the chip, as long as you keep your average power (on the scale of seconds or minutes) below the TDP. Indeed, many devices like laptops, tablets, and cell phones rely on this for maximum performance; if you load a web page, the CPU will ramp up well above the sustained TDP in order to render the page, relying on the fact that the CPU will be nearly idle or off while you read the page after it has rendered, so the average power will be below the TDP.

Instead, there is a different parameter - sometimes referred to as EDP. This tells you the power that the power supply needs to be able to provide, more on the scale of milliseconds (so a long enough timescale that the capacitors on the board can't keep up with the power demands, but not so long that the TDP starts to limit you). EDP is always higher than the TDP.

As I said, I don't build my own computers though (I just design them ;-)), so I have no idea if that's something that has worked its way into choosing a power supply yet. It doesn't seem like it, from some googling.

Other things that can make a difference are inrush current and power factor. I have a desktop that has about a 950W power supply. Typical power draw is on the order of 150 watts or so. So you'd think that a quality UPS with a 900 VA rating should be plenty - unfortunately, when powering it on or waking it, either the inrush current or the power factor as it charges all the inductors and capacitors in the power supply exceeds the capacity of the UPS about one in every 10 times. In that case, the UPS lights up its "Overload" light and shuts off, which rather negates the whole point of a UPS. Additionally, because turning on a light switch with a lot of CFLs often causes enough disturbance to the power to trip the UPS, and the UPS activating causes it to wake the computer, it happened that turning on a light switch would often cause my computer to be immediately disconnected from power, as it would hit the overload condition.

So I moved the UPS to my TV and network connections, and put my computer back on a surge protector. Everything is much happier now.

Comment: Re:Ehhh Meh (Score 4, Informative) 127

by Macman408 (#48394539) Attached to: US DOE Sets Sights On 300 Petaflop Supercomputer

There are plenty of things that can use all the computing power you can throw at it these days. As you mentioned, weather forecasting - though more generally, climate science. Somebody from one of the National Labs mentioned at a college recruiting event that they use their supercomputer for (among other things) making sure that our aging nukes don't explode while just sitting in storage. There are thousands of applications, from particle physics to molecular dynamics to protein folding to drug discovery... Almost any branch of science you can find has some problem that a supercomputer can help solve.

Additionally, it's worth noting that these generally aren't monolithic systems; they can be split into different chunks. One project might need the whole machine to do its computations, but the next job to run after it might only need a quarter - and so four different projects can use the one supercomputer at once. It's not like the smaller computing problems end up wasting the huge size of the supercomputer. After all, many of these installations spend more in electricity bills over the 3- or 5-year lifetime of the computer than they do to install the computer in the first place, so they need to use it efficiently, 24/7.

Comment: Re:As I think has already been pointed out (Score 1) 286

by Macman408 (#48218427) Attached to: Tech Firm Fined For Paying Imported Workers $1.21 Per Hour

I think that's where the determination of willful violation versus accidental can make a difference. Sure, if they knew they were violating the law and did it anyway, then they absolutely deserve a bigger punishment. If it's just a case where they didn't really consider the implications of bringing foreign employees to their US office, a small penalty isn't unreasonable. If they weren't willfully violating the law, they're more likely to follow it for its own sake, rather than due to a financial threat.

Comment: Re:$3500 fine? (Score 5, Interesting) 286

by Macman408 (#48216835) Attached to: Tech Firm Fined For Paying Imported Workers $1.21 Per Hour

It's not clear to me that it was willful avoidance of paying minimum wage - they had a job to do, they got help from some of their existing employees from overseas, who continued to receive their regular wage (in their regular currency) during the time that they were here. So the company paid the back wages to the employees, and a small fine to the government. Doesn't seem unreasonable to give them a little slap on the wrist; save the big punishments for when there are repeated offenses, or more wanton abuse.

I'm more curious what the legal requirement is for paying the local minimum wage instead of a worker's regular salary, when they are working away from their normal office. I certainly wouldn't want to be paid in rupees if I had to travel to an office in India. But if I were there under the same conditions as those workers were here, would there be any violation of US Labor Laws if they paid me the local wage while I was over there? On the other hand, if I go to a college recruiting event in San Francisco for an afternoon, am I entitled to an increased minimum wage of $10.74 for a few hours? What if I'm a driver, paid by the mile, going through different jurisdictions each with their own minimum wage law?

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