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Submission + - GRIZZLY STEPPE: Technical report on DNC hack (nymag.com)

schwit1 writes: Following weeks of accusations and insinuations — and counterclaims and skepticism — about the role of the Russian government in this summer’s hack of the Democratic National Committee’s email (an attack given the evocative name “GRIZZLY STEPPE” by the Department of Homeland Security) a new joint report was published today by the DHS and FBI. The question is, does the new report actually clear anything up?

Submission + - Facebook Buys Data From Third-Party Brokers To Fill In User Profiles (ibtimes.com)

An anonymous reader writes: According to a report from ProPublica, the world’s largest social network knows far more about its users than just what they do online. What Facebook can’t glean from a user’s activity, it’s getting from third-party data brokers. ProPublica found the social network is purchasing additional information including personal income, where a person eats out and how many credit cards they keep. That data all comes separate from the unique identifiers that Facebook generates for its users based on interests and online behavior. A separate investigation by ProPublica in which the publication asked users to report categories of interest Facebook assigned to them generated more than 52,000 attributes. The data Facebook pays for from other brokers to round out user profiles isn’t disclosed by the company beyond a note that it gets information “from a few different sources.” Those sources, according to ProPublica, come from commercial data brokers who have access to information about people that isn’t linked directly to online behavior. The social network doesn’t disclose those sources because the information isn’t collected by Facebook and is publicly available. Facebook does provide a page in its help center that details how to get removed from the lists held by third-party data brokers. However, the process isn’t particularly easy. In the case of the Oracle-owned Datalogix, users who want off the list have to send a written request and a copy of a government-issued identification in the mail to Oracle’s chief privacy officer. Another data collecting service, Acxiom, requires users provide the last four digits of their social security number to see the information the company has gathered about them.

Comment Correlation between Antibiotics and Obesity? (Score 3, Interesting) 256

On a hunch I decided to see if there's a correlation between obesity and antibiotics (which are known to kill both the good and bad types of gut bacteria)

Here's a map showing antibiotic prescribing rates.
http://www.cdc.gov/getsmart/co...

Here's a map showing obesity rates:
https://www.maxmasnick.com/med...

Correlation is not causation, but in my unprofessional opinion, these maps look eerily similar.

Comment Re:Useless Change (Score 3, Informative) 383

One more MAJOR advantage of a camless design (if not the single greatest advantage) would be the ability to have extremely canted valve angles. Retrofitting an existing cylinder head design with camless engine technology is only scratching the surface. The biggest benefits would be gained by designing the cylinder head ports around the capabilities of the valve actuators. With cylinder head differences like this, we're literally talking about the difference between NASCAR horsepower levels and streetcar horsepower because cylinder head designs are the undisputed most important factor in making horsepower.

With traditional cylinder heads (on OHV engines), valve angles are limited by the rocker arms. Rocker arm rotation about one axis is trivial, but when the valve is canted it makes the valvetrain design exponentially more complex and prone to wear due to lateral loads as the angle is increased. A camless engine design wouldn't have this limitation. That being said, the camless designs have their own challenges, namely soft valve seat landings due to a nearly perfect square-wave lift profile.

Comment Re:Don't understand engines, eh? (Score 4, Informative) 383

They call it a "Digital Cam" because when you graph valve lift vs time it literally looks like a square wave. The ramps really are that steep!

This compares to a conventional cam with a sudo-sinusoidal shaped wave lift profile (neglecting the effects of high RPM valve float).

Criticize as much as you want, but a truly functional electronically controlled camless engine would be the holy grail of internal combustion engine design. You can easily pick up 20 horsepower on many engines just by swapping to a performance cam, but you often compromise efficiency. But with a camless engine, in theory, you could have cylinder deactivation, low compression starts, the elimination of throttle plates (lower pumping losses), "full race-cam" profiles for performance, a cam profile for smooth idling, low emissions, etc....
Truly the best of both worlds!! That being said, there are disadvantages....

---

I read an interesting SAE paper 20+ years ago describing a working prototype camless engine. The performance gains were impressive, but as I recall, there were two main obstacles:

1) Noise, Vibration, and Harshness. (NVH)

2) The valves landed harshly leading to valve seat wear. The SAE paper suggested using a method for softer valve landings.

Comment Too ambitious (Score 2) 75

3D printing hype is getting out of hand.

Why would anyone buy an unfinished looking $53,000 3D-printed car like THIS, when you could buy a 500+ horsepower 2016 Shelby GT350 for about the same price? The resale value alone would make the 3D printed choice foolish.

If 3D printing was as promising as this article makes it sound, then why can't I buy individual parts like custom 3D printed hoods? It's certainly more realistic to buy individual parts than 3d printing an "entire" car. It's just not anywhere close to being cost effective.

Submission + - Microsoft's 1TB Surface Book will cost you a hefty $3,199 (engadget.com)

logaecology writes: Microsoft talked about the Surface Book having up to a 1TB solid-state drive when it announced the laptop/tablet hybrid, but you couldnt actually buy it on launch — 512GB was as good as it got. Well, that extra-capacious model is now available fo...

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