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Comment Re:Quick note (Score 4, Informative) 37

Nope, you need the reference phase to still be coherent with the observed object (temporal and spatial), so the interference is only possible between two parts of the same wave (of light), different in space (think two pinholes in a plane through which you collect the light) and/or in time (think delay line, let one part of the line you collected run a longer distance). The first is the famous Young's double slit experiment, the second is the Michelson interferometer.

Also, for reference : frequency of the visible EM fields is in the order of 300THz (300,000GHz).

Comment Quick note (Score 5, Informative) 37

This telescope operate in the radio bands (sub-millimeter) and not in the visible. That's why it is easy to make interferometry over very long base line. In the visible domain this is very tricky to realize over a couple of 100m (such as with the VLTI).

You can think of it as completing piece by piece the Fourier transform of the image you want to observe. Every pair of telescope gives you a measurement in the so-called UV plane (spatial frequencies). The furthest the observations point are (the telescopes) the smaller details you can get. Except this is only valid if you can measure the amplitude and phase of the electromagnetic radiation (or find a way to reconstruct it in some way). This is easy in the radio bands. But this oscillation is just too fast with visible wavelength and thus, we can not record and adjust offline, we have to interfere the waves right away...

Submission + - iOS WiFi Bug Allows Remote Reboot Of All Devices In Area 2

BronsCon writes: A recently disclosed flaw in iOS 8 dubbed "No iOS Zone" allows an attacker to create a WiFi hot spot that will cause iOS devices to become unstable, crash, and reboot, even when in offline mode. Adi Sharabani and Yair Amit of Skycure are working with Apple for a fix; but, for now, the only workaround is to simply not be in range of such a malicious network.

Submission + - Drone Killed Hostages From U.S. and Italy 1

HughPickens.com writes: The NYT reports that President Obama has offered an emotional apology for the accidental killing of two hostages held by Al Qaeda, one of them American, in a United States government counterterrorism operation in January, saying he takes “full responsibility” for their deaths. “As president and as commander in chief, I take full responsibility for all our counterterrorism operations,” including the one that inadvertently took the lives of the two captives, a grim-faced Obama said in a statement to reporters in the White House briefing room. The White House earlier released an extraordinary statement revealing that intelligence officials had confirmed that Warren Weinstein, an American held by Al Qaeda since 2011, and Giovanni Lo Porto, an Italian held since 2012, died during the operation. Gunmen abducted Warren Weinstein in 2011 from his home in Lahore, Pakistan. They posed as neighbors, offered food and then pistol-whipped the American aid worker and tied up his guards, according to his daughter Alisa Weinstein.

The White House did not explain why it has taken three months to disclose the episode. Obama said that the operation was conducted after hundreds of hours of surveillance had convinced American officials that they were targeting an Al Qaeda compound where no civilians were present, and that “capturing these terrorists was not possible.” The White House said the operation that killed the two hostages “was lawful and conducted consistent with our counterterrorism policies” but nonetheless the government is conducting a “thorough independent review” to determine what happened and how such casualties could be avoided in the future.

Comment News for nerds? (Score 5, Informative) 28

They are more art than science, providing an illusion of reality.

Nope, they are coded with the relation color = abundance of atomic component. Colors are a stimulus, they do not exist outside of all of our brains. What is real is the wavelength, and that, for instance, the transition of an electron from the 3rd to 2nd layer of the structure of the Hydrogen atom will emit a photon at 656nm, which we call red.

One disadvantage of the FITS format is that raw images typically need to be manipulated to show anything.

Nothing to do with the FITS format. That's the same type of information all RAW formats have : unprocessed data, as close as possible to the signal coming from the sensor after quantization, with ideally no processing, offset or other adjustments performed.

It made for great imagery, but wasn’t a true representation of how Jupiter looks.

Our vision is also subjective, it permanently adapt to lightning and ambient color conditions. There is no such thing as a true image representation. Especially in the mentioned case (a magazine), where it is desirable to have an image which pops the eye rather than a blob of washed out colors.

So what's the news here?

Submission + - LAUSD OKs Girls-Only STEM School, Plans Boys-Only English Language Arts School

theodp writes: Citing statistics that showed a whopping 46 more boys than girls passed the AP Computer Science Exam in 2011-12, the 640,000+ student Los Angeles Unified School District (LAUSD) on Tuesday approved a waiver to enable the District to operate a single-gender, all-girls STEM School called the Girls Academic Leadership Academy (GALA). Students in GALA will follow a six year sequence of computer courses starting in middle school that will culminate in AP Computer Science Principles. "Fewer females take AP courses in math, science, or computer science, and they are not as successful as males in receiving passing scores of 3, 4 or 5," argued the General Waiver Request (PDF, 700+ pages). "An all girls environment is reasonably necessary for the school to improve the self-confidence of girls in their academic abilities, especially in STEM areas where an achievement gap currently exists. GALA's admissions shall also comply with AB 1266 to ensure male students who identify as female are admitted to the school." The school's CS-related Partners include the UCLA Exploring Computer Science Program, as well as Google-bankrolled Girls Who Code, Black Girls Code, and NCWIT. One of the reasons the all-girls STEM school reportedly got the green light is that its backers satisfied federal regulations requiring a "substantially equal school" for excluded male students by submitting a plan for a companion all-boys school that would emphasize English Language Arts, where they often fall short of girls' test scores, rather than GALA's focus on STEM. One suspects the no-fan-of-gender-restricted-public-schools ACLU may call BS on this maneuver.

Submission + - MIT's Picture Language Lets Computers Recognize Faces Through Inference (itworld.com)

itwbennett writes: MIT researchers are working on a new programming language, called Picture, that could radically reduce the amount of coding needed to help computers recognize objects in images and video. It is a prototype of how a relatively novel form of programming, called probabilistic programming, could reduce the amount of code needed for such complex tasks. In one test of the new language, the researchers were able to cut thousands of lines of code in one image recognition program down to fewer than 50.

Submission + - US Blocks Intel From Selling Xeon Chips To Chinese Supercomputer Projects (itworld.com)

itwbennett writes: U.S. government agencies have stopped Intel from selling microprocessors for China’s supercomputers, apparently reflecting concern about their use in nuclear tests. In February, four supercomputing institutions in China were placed on a U.S. government list that effectively bans them from receiving certain U.S. exports. The institutions were involved in building Tianhe-2 and Tianhe-1A, both of which have allegedly been used for 'nuclear explosive activities,' according to a notice (PDF) posted by the U.S. Department of Commerce. Intel has been selling its Xeon chips to Chinese supercomputers for years, so the ban represents a blow to its business.

Submission + - Amid Controversy, Construction of Telescope in Hawaii Halted

An anonymous reader writes: After more than a week of demonstrations and dozens of arrests, Hawaii Gov. David Ige said Tuesday that the company building one of the world's largest telescopes atop Hawaii's Mauna Kea has agreed to his request to halt construction for a week. 'They have responded to my request and on behalf of the president of the University and the Office of Hawaiian Affairs have agreed to a time out on the project, and there will be no construction activities this week,' Ige said at a news conference. Thirty Meter Telescope is constructing the telescope on land that is held sacred to some Native Hawaiians. Scientists say the location is ideal for the telescope, which could allow them to see into the earliest years of the universe. Ige said he hopes the temporary pause in construction will allow the interested parties to have more discussions about the project. Native Hawaiian groups have been protesting the construction of the telescope since its inception last year.

Submission + - Slashdots stops sucking effective immediately!!

GrabbaTheButt writes: In a complete 180 degree turn of events, the overlords at Dice have decided to end all Slashvertisments, kill Beta and end all stories that have no place on this site.

When asked why such a radical change? Management said "we have decided to start listening to our user community and stop thinking straight out of our asses".

Comment Re:STL (Score 1) 757

1. Check whether a string s ends with a suffix t.

What about :
!s.empty() && s.back()=='t'
Or, before C++11 :
!s.empty() && (*s.rbegin())=='t'

2. Check whether a collection c contains an element e.

For this one, the C++ implementation makes more sense than the other too : you can immediately store, test and work on the iterator and not wasting your time checking if the element is in the container, then find it again to work on it. If you don't need to use it, you can use std::count (because your container might contain it multiple times) as :
std::count(myContainer.begin(), myContainer.end(), theValue)>0
Or if you know that the element can only be present once, you should be using a std::set as container which already has a count function which only returns 0 or 1.
mySet.count()>0

Split a string s into tokens based on whitespace.

std::string is still not very high level. Good parsing almost requires regexp methods which C++ did not have until recently (in the standard).
Otherwise, the first solution given in your link is verbose but does the job.

Do you have any other good examples?

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