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Comment: Re:Here's the bill: public notice key (Score 2) 107

by Sarten-X (#48026793) Attached to: California Governor Vetoes Bill Requiring Warrants For Drone Surveillance

The last word is probably the most damning.

There's a very popular school of thought in security that keeping capabilities secret is a means to reduce risk*. Such a vague requirement to disclose capabilities is open to lawsuits arguing that the disclosure must include things like maximum range, speed, radar size, and so forth, effectively providing an instruction manual for criminals looking to evade such a drone, who now know that their escape plan must include driving so fast for so far.

* No, it's not security through obscurity. Security through obscurity is where the security of the system is compromised by knowledge, whereas keeping the capabilities of a secure system secret only increases the expense (and therefore lowers the chance) of an attack against an otherwise-secure system.

Comment: Re:Should we? (Score 2) 261

by Sarten-X (#48012281) Attached to: Could We Abort a Manned Mission To Mars?

...but we know it's not mapped. We've mapped a good chunk of sea floor, and figured out what to expect. Maybe we could find some new geologic features or something, and those biologists still have a lot of work to do naming everything, but we know more or less what's down there. For an oceanographer, saying "I have no idea what's there" is a sign that you haven't done your research, not that we've hit the limits of our instruments. That's still a valid justification for space exploration, though. We have no idea what other worlds are like, because we haven't sent enough probes and instruments to find out. We simply don't know what's under those clouds, or what that surface is made of, or why that moon is that particular color.

Comment: Re:Should we? (Score 4, Interesting) 261

by Sarten-X (#48012145) Attached to: Could We Abort a Manned Mission To Mars?

I will never understand the quasi-religious fervor some people have about space.

It's not about space. It's about not-Earth.

For most practical purposes, Earth has no more undiscovered continents, no more unexplored territory, and no more absolute wilderness. Sure, there's some areas that are generally undisturbed, but we know just about all there is to know about them. There are no more mysteries lying just beyond the horizon. There is only human civilization. There are cell phones, satellites, and rescue teams standing ready. Human exploration is at a standstill.

There are some places left to go to fill in the gaps in our knowledge. We can cut deeper into the jungles, and dive deeper into the oceans, but we still know what we don't know.

The next horizon for humanity's exploration is space. That's where we'll next spread our human empire, and for those who care about such things, the enthusiasm for space is natural.

Comment: Re:Sierra Nevada - - I love their beer! (Score 1) 126

by Sarten-X (#48011961) Attached to: Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

This is how government contracts work.

Including the lawsuit phase, which is really the only chance the companies have to compete openly. Bids are usually keep secret from the competitors until a contract is awarded, so if they want to directly compete and argue their benefits over another's offer, the loser asks for a review.

This is business as usual.

Comment: Re:Useless (Score 4, Interesting) 302

by Sarten-X (#48010015) Attached to: Consumer Reports: New iPhones Not As Bendy As Believed

Torque is what matters.

If you test bending in the middle, you put 70 pounds force (approximately 300 newtons) in the middle, and support the ends firmly. That means that if the weakest point is in the middle, the torque on that point is (2 x 150 newtons x 80 mm), as the length of the lever arm to the support at the edge is about 80 mm. We'll ignore the fact that the test support is really a little bit inside that, and assume that the subject is supported right at the edge. Note also that the force is 150 newtons, which is half of the 70 pounds force used to break the phone, because the force is opposed evenly by two supports. Their equal force is then summed, which is why our total torque has that "2" scalar, giving us a total of 24 newton-meters of torque.

If we bend off-center, such as half-way towards one of the ends, the forces on the test supports are no longer equal. Our lever arms are now 120 and 40 mm, and the force would be unevenly distributed as well. The force is distributed inversely to the length of the lever arms, so the short arm, being 25% of the length, now supports 75% of the load, which is 225 newtons. The long arm supports 25%, which is 75 newtons. This gives us a total torque of (225 newtons * 40mm + 75 newtons * 120mm), for a total of only 18 newton-meters of torque.

Since testing off-center actually applies less torque to the test subject, the question then becomes one of whether the weak point is really 25% weaker than the rest of the beam.

However, we can also compute the torque on the supposed weak point during the center test. In that case, the lever arms can be computed as though they behave as a typical lever, scaling the force. they apply. The longer lever would be a class 3 lever, which would reduce the effective force of the test to 100 newtons. On the other hand, the shorter arm would behave as a class 2 lever, increasing the force to 300 newtons. The total torque on the weak point during a center test, then, is (100 newtons * 120mm + 300 newtons * 40mm), which is again 24 newton-meters.

If the weak point were really weaker than anywhere else in the phone, it would break during the center-loaded test. Looking at the pictures from Consumer Reports, though, that's exactly what happened. On both the iPhone 6 and iPhone 6 Plus, the most significant damage is at the edge of the volume buttons closest to the center.

However, it's worth noting that the Consumer Reports test was conducted until the screen detached, even if that happened after the phone itself was permanently deformed. Looking at other pictures of bent phones, their screens have not separated from the cases, so they likely used less force to deform. Bending to separation, though, provides a consistent point of comparison to other phones, which may have internal damage even if their cases return to normal.

Disclaimer: I am not a physicist, and not a test engineer. If my math or methodology is incorrect, please feel free to tell me why.

Comment: Re:The stress-testing wasn't needed (Score 1) 147

by Sarten-X (#48007035) Attached to: PostgreSQL Outperforms MongoDB In New Round of Tests

Was that even transactional?


The live results were restricted to simple queries (mostly for internal reporting), but the workload to be performed ultimately was more straightforward map-reduce algorithms. Everything (live and final) was statistics, so missing a few records due to lacking ACID wasn't ever a real concern.

That almost sounds like a use case for Kx or similar stuff.

It's been a while, but I believe Kx was considered during the initial research phase. Ultimately Hadoop and HBase fit our needs better.

Comment: Re:The stress-testing wasn't needed (Score 4, Insightful) 147

by Sarten-X (#48003909) Attached to: PostgreSQL Outperforms MongoDB In New Round of Tests

I've worked extensively on both kinds of systems over the past decade. Under a particular workload that is exactly what an RDBMS is designed for, an RDBMS has the best performance? Wow, who would have bet on that one?

Then again, I've had workloads (my go-to example is writing several billion records in a matter of hours for statistical analysis, with live intermediate results) where a NoSQL solution had the best performance.

NoSQL isn't some rebellion against traditional databases. Engineering isn't a contest. Rather, NoSQL, column-stores, distributed warehousing, or any other term you'd like to throw out all just point to an additional option for how to manage your data. Pick the right choice for your project, and use it. Don't worry about "web-scale" or "ACID compliance" talking points unless your project needs them. For the past few decades, we've been forced into the assumption that data must perfectly normalized, arranged in tables, and must be queried as relations. For some projects, massaging the data into that form will damage your performance far more than your database engine ever will, so a different engine makes a better choice.

Stop listening to hype, deserved or not, and use the right tool for the job.

Comment: Re:The WHO (Score 1) 478

by Sarten-X (#47968885) Attached to: Bioethicist At National Institutes of Health: "Why I Hope To Die At 75"

Is that so bad, though?

Let's say, hypothetically, that if you spend an hour exercising each and every day for 40 years, you can extend your life by an extra decade. Assuming a constant 8 hours of sleep daily, that's a four-fold return on investment!

Of course, due to the effects of aging, it very well could easily take me twice as long to do anything, and I could easily get only half as much enjoyment out of it. Sure, I keep pushing that number higher, but by a self-assessment of how good my life is, I'm only breaking even. Considering the risks associated with aging, is it even worth the investment?

My grandmother has said many times that the only thing wrong with her is that she hasn't died yet. She's well into her 90's, with no serious physical deterioration, but life has gotten boring. Her life-long friends have all died, and many of her new friends have died, too. Her children have grown up and moved on, and so have her grandchildren. She's traveled the world multiple times, and gone on every adventure that she wanted to. She was expecting to die twenty years ago, having lived a complete and happy life.

Now what's left? Seeing yet another round of new miracles being taken for granted by a generation that assumes such technology is a basic necessity for life? Watching $THIS_GUY slaughter $THOSE_GUYS in the name of $SUBJECTIVELY_JUST_CAUSE? Spending another year alone in her home?

More personally, I have a medical condition that will deteriorate rapidly when I hit about 50, and faster if I partake in strenuous exercise. The only treatment option includes the term "replacement vertebrae". Is it somehow morally wrong for me to plan my life such that I spend every waking moment now using my limited health in ways that I enjoy the most? I doubt I'll survive as long as my grandmother, and my condition effectively assures me of problems by that age, anyway. Hitting 75 and signing off sounds like a good plan to me.

Comment: Re:Your employer (Score 1) 182

by Sarten-X (#47965149) Attached to: Ask Slashdot: Who Should Pay Costs To Attend Conferences?

I have to agree here. The submitter should talk to their boss again, and keep asking, trying to work out something acceptable. An agreement to stay at the job for some amount of time can alleviate fears of competitors hiring away fresh knowledge, for example. If the company's as small as is implied, that may be feasible.

I've rarely had requests approved on the first try, but changing companies because they didn't want to fund a weekend bender in Vegas is absurd. Make a case for your requests, and present it as an investment cost for the business.

Comment: Re:It costs power (Score 4, Insightful) 262

by Sarten-X (#47953635) Attached to: Why the iPhone 6 Has the Same Base Memory As the iPhone 5

That's about right. I just checked my iPhone (4s), and in over two years of use, never cleaning anything, I've barely passed 5GB. By far the biggest use of space is recorded videos, followed by photos, then several big apps.

I'm not going to say "16 gigabytes ought to be enough for anybody," but it is enough for many people right now. Maybe they use ICloud, or maybe they're following good habits to move photos off of their easily-lost phone, or maybe like me their primary usage model is streaming and other ephemeral data. I just don't see a pressing need to add more memory on the low-end model. There doesn't have to be some sneaky marketing plan to say "this is good enough for now."

Comment: Re:Nostradamus (Score 2) 183

by Sarten-X (#47936857) Attached to: Snowden's Leaks Didn't Help Terrorists

The first poem is clearly referring to someone else.

East of the Apennine would refer to the Arabian desert, so it's about a man who left his desert home, flew to a wet area for training, then spent time in a snowy area. He would be a great warrior, mostly using a stick-like weapon, rather than projectiles.

Nostradamus was telling the tale from "a long time ago"; that of Luke Skywalker.

It's been a business doing pleasure with you.