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Comment: Epic fail: someone always matches (Score 2, Interesting) 128

by davecb (#49810955) Attached to: China Unveils World's First Facial Recognition ATM

This scheme will work for one branch in Lesser Nowhere, Sechwan Province, with a finite and small set of pictures, and a small number of crooks. Once the number of faces increases, the probability of a false positive explodes, roughly as (N 2) (select every two out of N), where N is the size of the pools of pictures + the person being scanned.

The well-known example is the "birthday paradox", in which twenty-three people at a party increases the probability of two of them having the same birthday to fifty-fifty. That particular case was because the actual probability was multiplied by (25 2) = 25! / ((25-2)! * 2!) = 6900 comparisons being made, times 1/365 chances of a hit.

The German federal security service considered using one of my then employer's recognizers for airports to catch terrorists, but ended up facing the problem of accusing grandma of being part of the Bader-Meinhoff gang (;-)) No matter how accurate we were, a few more people in the pool would give us false positives. We'd need roughly an accuracy of 99.9 followed by roughly as many decimal places of 9s as there were powers of ten of people.


Comment: many recruiters are hired off the street (Score 1) 227

by davecb (#49598115) Attached to: Want 30 Job Offers a Month? It's Not As Great As You Think
A sister company did recruiting, and a then colleague said "I asked for a MVS and Unix person in a particular state with experience in a package", and got hundreds of names, none of whom knew all those things". The didn't know the difference between "and" (3 candidates) and "or" (3000 unqualified candidates). I still get requests for things I only ever did once, with co-requisites of things I've never done...

Comment: Re:Help me out here a little... (Score 1) 533

by davecb (#49506283) Attached to: Utilities Battle Homeowners Over Solar Power

I think you'll find that electricity won't flow out of the solar supplier if the voltage in the line is at 120v, as there's nowhere with a lower voltage for it to flow to. Anyone who draws current from the system creates a region of lower voltage, and current flows toward them until the voltage is the same everywhere. Think of it electricity as being rather like water in a sealed watertower: no more flows in if it's full, plenty flows out if someone lowers the pressure by opening a tap.

Therefor the spike from all the solar installations just offers more power. If no one takes it, current doesn't flow, the solar folks' ammeters don't budge and they don't get paid by the power distribution company. If somebody turns on a light, current flows, and some supplier's ammeter moves, usually a supplier close to the lightbulb. Ditto the consumer's ammeter, what we call the "electric meter"

Comment: They have to put in safety equipment in any case (Score 4, Interesting) 533

by davecb (#49504939) Attached to: Utilities Battle Homeowners Over Solar Power
To connect a power source to the grid, there has to be a cutoff that disconnects it when the grid voltage drops to zero due to, for example, a tree falling and shorting it to ground. If there isn't a cutoff
  • - the grid sucks all your power and probably blows your fuses and/or rectifier diodes, and
  • - the hydro guy who expects to be handing a dead line suddenly has it jump to 110 or 220V, the instant he lifts it off ground.

Linemen don't like becoming part of the circuits, so they successfully called for the disconnect-if-zero laws.

Power companies (at least in Canada and large parts of the world) already have equipment to deal with the fact that the power can flow both ways. In fact, claiming they don't have equipment is only true IFF the power companies are the ones who like electrocuting their employees (;-))

+ - Politics Poisoning NASA's Ability To Meet Its Goals-> 1

Submitted by Anonymous Coward
An anonymous reader writes: Phil Plait just published an article showing how politics is interfering with NASA's ability to perform vital scientific experiments. As expected when we heard that Ted Cruz would be made head of the committee in charge of NASA's funding, the Texas senator is pushing hard for NASA to stop studying Earth itself. Plait writes, "Over the years, NASA has had to beg and scrape to get the relatively small amount of money it gets—less than half a percent of the national budget—and still manages to do great things with it. Cruz is worried NASA’s focus needs to be more on space exploration. Fine. Then give them enough money to do everything in their charter: Explore space, send humans there, and study our planet. Whether you think climate change is real or not—and it is— telling NASA they should turn a blind eye to the environment of our own planet is insanity." He concludes, "[T]he politics of funding a government agency is tying NASA in knots and critically endangering its ability to explore."
Link to Original Source

+ - FBI's Big Plan To Expand Its Hacking Powers

Submitted by Presto Vivace
Presto Vivace writes: DefenseOne reports:

the rule change, as requested by the department, would allow judges to grant warrants for remote searches of computers located outside their district or when the location is unknown.

The government has defended the maneuver as a necessary update of protocol intended to modernize criminal procedure to address the increasingly complex digital realities of the 21st century. The FBI wants the expanded authority, which would allow it to more easily infiltrate computer networks to install malicious tracking software. This way, investigators can better monitor suspected criminals who use technology to conceal their identity.

But the plan has been widely opposed by privacy advocates, such as the American Civil Liberties Union, as well as some technologists, who say it amounts to a substantial rewriting of the rule and not just a procedural tweak. Such a change could threaten the Fourth Amendment’s protections against unreasonable search and seizures, they warn, and possibly allow the FBI to violate the sovereignty of foreign nations. The rule change also could let the agency simultaneously target millions of computers at once, even potentially those belonging to users who aren’t suspected of any wrongdoing.

+ - Ask Slashdot: Do ITIL hates skilled people? 15

Submitted by ulzeraj
ulzeraj writes: First of all I would like to apologize about the language. I’m not a native english speaker.

I've been working with Linux and in a lower extent Windows setups for 10 years now. During most time of my career I've been involved with IT consulting firms. Last year I've joined a retail store company that was in dire need of someone with good debugging skills. Their team is awfully unskilled and during the course of the year I was able to improve a lot of their network and server systems including automation, backups and restore strategies, complicated image deployment strategies and so on. I've also worked in improving the performance of their database and ERP systems and solved every fucking problem they’ve thrown at my direction including some they didn’t really knew they existed. The company office was a great bazaar and overall fun to work and comfortable to boot because their needs were always simple for someone with my skills so in the end I would always blow their minds with the results. I should note that I never have problem with knowledge sharing and documentation.

But recently the managers were replaced and the new guys don't seem to like me. They are pushing for ITIL doctrine on the IT department (and the whole company afterwards). For starters they keep pushing me administrative tasks that I'm not really fond of like keeping in touch with our suppliers and managing project dependencies so I’ve been spending more time attending meetings and mailing people than typing on a terminal. I've heard somewhere that the cult of ITIL somewhat hates the "hero culture" and people like me are not really healthy for their dogmas and I’m considered a “risk". I feel that even as I have so much that I can do for the company I'll probably be cockblocked by their new "project management" department and whatnot.

As this is happening it seems that people on the IT consulting firms really like my job and there are plenty of oportunities around. I know many slashdoters like me that are more experienced have encountered similar situations. Do ITIL really creative and skilled people? Is my kind doomed to oblivion and I’ll face stuff like this anywhere I go?

+ - Deploying Solar in California's Urban Areas Could Meet Demand Five Times Over->

Submitted by Lucas123
Lucas123 writes: About 8% of terrestrial surfaces in California have been developed, ranging from cities and buildings to park spaces. If photovoltaic panels, along with concentrating solar power, were more effectively deployed in and around those areas, it could meet between three and five times what California currently uses for electricity, according to a new study. The study from the Carnegie Institution for Science, found that using small- and utility-scale solar power in and around developed areas could generate up to 15,000 terawatt-hours (trillion watt hours) of energy a year using photovoltaic technology, and 6,000TWh of energy a year using concentrating solar power technology. "Integrating solar facilities into the urban and suburban environment causes the least amount of land-cover change and the lowest environmental impact," post-doctoral environmental earth scientist Rebecca Hernandez said.
Link to Original Source

+ - Microsoft's 'Delve' Will Tell You What Your Co-Workers Are Doing With Office->

Submitted by jfruh
jfruh writes: Users of one of Microsoft's business-class Office 365 plans will soon have access to Delve, a feature designed to analyze how people work on Office 365 and automatically make relevant data on colleagues and content easily accessible. For example, using calendar information, Delve can determine that a user has a meeting in four hours, what topics will be discussed and who will participate, so the application collects documents, files and information it deems relevant and displays the content in the dashboard. Will this herald a new era of assisted collaboration, or is this just Clippy in the cloud?
Link to Original Source

Comment: Obstruction is a wild overstatement (Score 4, Informative) 340

Obstruction of justice is typically things like bribing witnesses, which is specifically mentioned in the law. Not refusing to unlock oa locked cell-phone, which the courts have held requires a warrant in other circumstances.

From the information in the article, this sounds like an attempt to scare a citizen into doing something.

Attempts to widen this particular law to cover less serious crimes get rejected by the courts: the very first case on the subject inCanII says (emphasis added)

[19] Moreover, an assertion that the mere attempt by an accused to identify an informant is a crime, fails to take into account that the types of conduct which constitute obstruction of justice, even though not fully articulated in the Criminal Code, are relatively well and narrowly defined in the law, and must remain so narrowly defined in order to have certainty in the law. Offences against the administration of justice have always included such conduct as attempting to influence a jury or to threaten a witness, or publishing sensitive information when a matter is working its way through the justice system, a general category of conduct which lawyers sometimes call an infraction of the sub judice rule. I have been unable to find a single suggestion anywhere in the law that an accused cannot take steps to identify a police informant; the court should act with restraint in opening new classes of obstruction of justice. Although obstruction of justice is an evolving concept, its main tendency is to narrow the categories of conduct which may constitute a crime rather than to enlarge them: Sunday Times. Recent examples of the narrowing of the categories include the removal of scandalizing the court as a matter of contempt, Kopyto, and the striking down of the publication ban on bail hearings, White.

Take an astronaut to launch.