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Comment Re:The caps are electrolytic (Score 1) 111

The regulators are there - you can see the 'big' coils in TFA. The capacitance for a simple "drain till you drop" scheme would have to be a lot here - very roughly 2*Energy/efficiency/(Vddmax^2 - Vddmin^2). So, step the voltage up optionally, keep the caps charged as high as practical, squeeze them dry when needed through a step-down converter.

TFA also says that the drive periodically monitors the "status" of the caps; I'm not sure if that means charge level or charge-holding capacity but it could test-discharge one cap at a time.

Comment Re:The caps are electrolytic (Score 4, Informative) 111

The caps only need to supply enough juice to sync the RAM buffers to flash to ensure consistency of its internal block-mapping metadata (the filesystem should handle the rest through journaling and whatnot). The caps are rated at 35v but let's assume that they're kept at 12v: E = (12 v)^2 * 47 uF / 2 = 3.4 mJoules. Even at full operating load that should last for half a millisecond counting losses, but when power goes out the drive is going to stop serving requests and all it has to do is write that 1 GB buffer to a few flash blocks. More than enough, methinks.

Comment Re:The caps are electrolytic (Score 4, Informative) 111

tl;dr: these are storage caps, which don't endure the ripple currents that kill filter caps.

Electrolyte decomposition is usually caused by high ripple current, which is why caps pop mostly (only?) when used as filters, as in motherboard DC-DC converters and gadgets powered by wall-wart adapters. In this particular application, the PSU impedance is quite low and the caps are handled by on-board regulators (V=Q/C and all that), so there's no load ripple and the caps just have to sit pretty and charged with insignificant heat losses until the computer is shut down or outage occurs. Maybe that's why Intel didn't even bother to use the solid (polymer) kind.

If these caps dry out due to age or bad quality they just won't hold as much charge for emergency sync'ing, which is still better than ordinary SSDs/HDDs with no caps.

Comment Re:Fly fishermen have used this property for years (Score 2) 111

Do you mean that the treated nylon re-twisted spontaneously upon heating? I already know that to make a tight knot on a stiff material you can soften it with heat, but this is about "shape memory" - twist, heat, relax; then it will coil up actively when heated:

Spinks says they attached the fishing line to an electric drill and applied tension to the thread.

As it twists, the fibre forms tight coils in a spring-like arrangement. Once heat is applied to the coils it permanently fixes that spring-like shape.

Spinks says to use these springs as artificial muscles heat is again applied, causing the whole coil to contract.

Comment Re:No evidence for censorship (Score 1) 152

Venezuela is just about the safest place for dissidents in Latin America, not the worst. For a start, consider "reporters without borders", they're a US-funded "freedom" lobby group. Very anti-communist.

Read their headlines about Colombia:
https://en.rsf.org/colombia.ht...

Now read their headlines for Venezuela:
https://en.rsf.org/venezuela.h...

The Colombian journalists problems are all murder, threats, intimidation by pro-government fascist death-squads.

The Venezuelan journalists problems are more along the lines of politics and bureaucratic red tape. And those are the WORST abuses that Reporters without Borders can highlight about Venezuela.

I don't know much about the threats on Colombia's journalism but I can tell you a few things about Venezuela. Trust me or call me a liar at your discretion:

* There are laws regarding "truthful and opportune information" and making "disquieting" and "destabilizing" speech a felony. Of course, no definitions for these fuzzy adjectives.
* Detention and/or beatings by military and govt-friendly gangs; it is not unusual for both to confiscate the memory cards and tapes. There's some mention of this in the RSF link you posted.
* One columnist was fined heavily for writing one of his pieces as a letter to Chavez's young daughter. Mind you, he didn't attack her in any way - he sympathized with the burden of being Chavez's daughter.
* The main opposition TV station, Globovisión, was accosted with fines (a recent amount was 10% of their gross revenue) for everything from donating airtime to broadcasting "disquieting" spots by NGOs. Eventually the station claimed being financially inviable and was sold to friendlier investors with a new editorial line, which has caused most reporters, interviewers and anchors to resign over the last year.
* In the months after the telecom regulator discretionarily revoked the broadcast license to another station, the gov't summoned the owners of two other stations with a milder but also critical stance. One became neutral-favorable, and the other came just short of a lap-dog.
* I hope you're aware about the tight controls on currency exchange. Well, every newspaper is facing a heavy shortage of currency for importing newsprint except state-sponsored and friendly ones. Maduro himself has yelled in public "not a single dollar more for the bourgeoisie!".

Now, ask yourself since Colombia is so much WORSE than Venezuela in protecting journalists, why do you never hear a peep in the media about how bad it is? Perhaps because there is no oil there?

*Ahem*

Oil - production: 588,000 bbl/d (93,500 m3/d) (2008 est.)
Oil - consumption: 267,000 bbl/d (42,400 m3/d) (2007 est.)
Oil - exports: 294,000 bbl/d (46,700 m3/d) (2008 est.)
Oil - imports: 12,480 bbl/d (1,984 m3/d) (2005)
Oil - proved reserves: 1,323,000,000 bbl (210,300,000 m3) (1 January 2008 est.)

Economy of Colombia

And oil shipments from Venezuela have been always on time, in spite of all the rhetoric.

Comment Re:No evidence for censorship (Score 1) 152

Here's a test from the state-owned ISP (CANTV) mentioned in TFA:

$ for host in lapatilla.com pastebin.com anonymouse.org; do ping -w 3 -c 4 $host; done
PING lapatilla.com (141.101.113.240) 56(84) bytes of data.
64 bytes from 141.101.113.240: icmp_seq=1 ttl=53 time=133 ms

--- lapatilla.com ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 133.576/133.576/133.576/0.000 ms
PING pastebin.com (190.93.241.15) 56(84) bytes of data.

--- pastebin.com ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2014ms

PING anonymouse.org (193.200.150.137) 56(84) bytes of data.

--- anonymouse.org ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2016ms

La Patilla is a popular opposition news site (slow but not actually blocked). Pastebin was used to distribute the links to some leaked emails last year. Anonymouse is quite popular with opposition Venezuelans trying to circumvent actual or perceived blockings.

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