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Comment: Re:You're doing it wrong. (Score 1) 166

Providing an answer inside of a deadline is an entirely different problem to knowing the current time, and you definitely do not need an accurate clock source to do it.

Even driving a car doesn't require split second timing. If it did, human's wouldn't be able to do it. That's why we've got the 2s rule...

Comment: You're doing it wrong. (Score 5, Insightful) 166

There is no "now" [1]. If you're relying on accurate timing from a network, you're already broken. If you require accurate local times, then you know that and know the error terms on your clocks. Standard OS clocks only tick at about 100hz, so you're always out by an average of 5ms anyways.


Comment: Re:Why worry about skyscrapers? (Score 1) 191

by Jason Pollock (#47747887) Attached to: Slashdot Asks: How Prepared Are You For an Earthquake?

Christchurch's earthquake resulted in building failures and caused loss of life. However, several buildings, while they later needed demolition, did stay up allowing evacuation.

The CTV building was the major failure, resulting in the death of 115 people (6 stories) [3]. A close one was the Hotel Grand Chancellor (26 stories) [2]. A frequent failure mode was the collapse of the stairwells [1].

However, you are correct, you are definitely safer being _inside_ a building. People who were on the street were killed by falling debris and masonry.



Comment: Re:You are NOT the product here. (Score 1) 167

Actually, there is a lot of room in between where intelligence can help the home owner substantially.

There are huge differences in incremental costs for power generation and lines. The cost of switching on a peaking natural gas turbine plant for peak power generation increases the cost of electricity by insane amounts, from $50-200/Mwh to $20,000/Mwh (NZ numbers).

So, providers implement time-of-day metering which roughly matches up with demand. It still doesn't match up with the provider's incremental costs, but it's a signal. What would happen if they could pass it back in much more fine grained fashion?

Take a look at your dominant sources of power consumption:

1) Hot Water Heating - if electric, this is 25% of the household bill.
2) Heating/Cooling - another 50%
3) Fridge - 5%

All those items can be shifted by _hours_ without changing your comfort. That's 80% of a household's load which can be shifted/shed in times of high cost. If only you knew!

Now, add in fine-grained demand metering and charging and then add a signal back to your devices.

Comment: You are NOT the product here. (Score 4, Informative) 167

The single biggest thing that power companies worry about is demand. Long term, short term. They worry about it second by second, millisecond by millisecond even. If someone has a better short term model they can make money.

This is why power companies worry about the weather so much. It has very little to do with the sun or the wind. Who cares if you're a coal/natural gas plant?!?

Except you do. The generators all have consents that say that the can only take a certain amount of water from the river for cooling, and they can only raise the temperature of the river a certain amount. That means the temperature of the water (and air) are very important. There is a direct correlation between weather and the amount of power they can generate.

Add to that demand prediction. Sure, they've got a model, and smart meters tell them when you are likely to use power (based on previous patterns). However, Nest's data will tell them when you are going to use power. 100%. Even better, Nest is able to _delay_ that power use, or shift it to when it is cheaper. It will even result in a more stable grid, since that data feed will allow the generator to know when there's about to be a brownout.

New Zealand already does this with "ripple control" on water heaters. Suppliers turn water heaters OFF at the meter when power prices get to high.

This is not about snooping on what you do (the power companies already know), it's about the grid itself.

Comment: IMEI blacklists already do this. (Score 2) 218

by Jason Pollock (#46621635) Attached to: Smartphone Kill-Switch Could Save Consumers $2.6 Billion

Databases already exist with stolen IMEIs. This will prevent those devices from registering on a carrier's network, rendering them wifi-only.

Both systems require the owner to report the theft, which you wouldn't do if your phone is >2-3 years old - value is > insurance deductible.

Since the existing systems are already not used, there won't be any change by any new system.

The response is that thieves change the IMEI number (which can be hard). What is says is that any new system would have the same result - the thieves would change the identification number used to lock out the device.

Comment: Similar. (Score 1) 983

by Jason Pollock (#46465435) Attached to: How Do You Backup 20TB of Data?

I've got a large collection of movies (12TB). My backups are the physical DVD/BluRay/CD media. It does take a bit of time to restore a 4TB drive, rips are typically about 1GB/minute for BluRay or DVD.

My recommendation: don't store the collection as a single RAID array. That way, when you lose the array (which will happen), you don't lose the entire collection.

Personally, I'm too cheap to pay for the extra drives to implement mirroring, so I just use JBOD.

Comment: Wooden chopping boards. (Score 5, Informative) 205

by Jason Pollock (#46368741) Attached to: Water Filtration With a Tree Branch

Trees are great at dealing with bacteria.

We soon found that disease bacteria such as these were not recoverable from wooden surfaces in a short time after they were applied, unless very large numbers were used. New plastic surfaces allowed the bacteria to persist, but were easily cleaned and disinfected. However, wooden boards that had been used and had many knife cuts acted almost the same as new wood, whereas plastic surfaces that were knife-scarred were impossible to clean and disinfect manually, especially when food residues such as chicken fat were present.


Comment: Re:Where did the money go? (Score 4, Informative) 501

by Jason Pollock (#45126035) Attached to: Lessons From the Fiasco

It's a website that needs to be able to handle 3million visitors per day, with the majority of them being signups, or at least hitting the calculator. That's a lot of deep hits that can't be cached.

Then, add on a back-end that has to talk to insurance companies. These guys still have a tonne of Cobol code running around. There's nothing wrong with that (Seinfeld!), but I think it might indicate that their systems aren't necessarily built for online, real-time querying.

To recap, it is a multi-tier system:

1) Front end, performing user signup, and calculator.
2) Back end database. HIPA compliant, Sarbanes-Oxley compliant and able to deal with 100m customer records.
3) Feeds to remote systems, also HIPA compliant, Sarbanes-Oxley and other stuff.

So, you've got something that looks a lot like twitter (the back-end links), only more expensive because it needs to be Capital S secure, along with something that looks like an insurance company (the middle tier) and finally something that looks like a dot-com (front end calculator).

That's already a lot of hardware and software. "Free" open source doesn't actually save a lot of money here, since most of the money is in support (over 1/2 the 5year cost!). Now, triple it do deal with hot site failover, backups and other various disaster recovery plans.

Although they've had 3 years to get the system complete, the software was probably only developed in the last 10-12 months (at most). The rest of the time would have been spent in getting agreement on the data exchange formats with the insurance companies, deciding on a vendor to use for each part, and standing up an internal team to manage it. Then add in several parties involved playing schedule chicken with Congress, hoping for the whole thing to either be delayed or scrapped. Fun!

Finally, they went for a nationwide rollout for political reasons, which was guaranteed to result in peak traffic on day 0.

Comment: Re:Doesn't mean you can copy it. (Score 2) 216

If what you say is true, Steamboat Willie, as well as Fantasia are both out of copyright in the UK. I wonder why no one has started selling copies?

The first time I saw the whole "50 years on fixed performances", I went "YAY! I can put them online!" Thankfully I talked to a lawyer who told me that the script and music rights are transitive and _not_ extinguished by being embodied in another work.

Of course, my IP lawyer might have been wrong. Personally, I'd love for you to be right. How about you put something up in the UK and see what happens?

Promising costs nothing, it's the delivering that kills you.