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Yunliang Yu, IT Senior Manager

Yunliang Yu

Open source is an investment in the future.

FDS Motto: we serve and empower the faculty.

Contact Info:
Office Location:  029D Physics
Office Phone:  (919) 660-2803
Email Address:   send me a message
Web Page:   http://www.math.duke.edu/~yu

Office Hours:

12:01AM - 12:02AM every other day except today.
Not by appt :-)
Specialties:

Mathematics
Recent Publications

  1. Y. Yu, test 123 (March, 2010). [PNG, PDF]

Famous Sayings:
Your dream will come true, if you eat your soup.
    --- Angela Yu
Don't be a turkey; read a book.
    --- Christina Yu
Security = avoid "unexpected inputs for unintended results".
    --- moi
To learn and practice what is learned from time to time is pleasure, is it not? To have friends from afar is happiness, is it not? To be unperturbed when not appreciated by others is a gentleman, is it not?
    --- Kungfu Zi
Better to light a candle than to curse the darkness.
    --- Chinese Proverb

mathprograms.org, academicjobsonline.org, mathjobs.org, ShortURLs, sharedworkingplace.org, chinesecalligraphyandwoodcarving.

/. headline news :-)

  • How Uber Surge Pricing Really Works
    2015-04-19T17:16:00+00:00
    minstrelmike writes with this analysis from Nicholas Diakopoulos of the Washington Post: At the core of Uber's wild success and market valuation of over $41 billion is its data and algorithmically fueled approach to matching supply and demand for cars. It's classic economics, supposedly....but is Uber's surge pricing algorithm really doing what they claim? Do surge prices really get more cars on the road? My analysis suggests that rather than motivating a fresh supply of drivers, surge pricing instead re-distributes drivers already on the road. Adds minstrelmike: The writer goes on to analyze 4 weeks of pricing info from 5 areas in D.C. and plotted prices versus wait times. "Price surging can work in any of three ways: by reducing demand for cars (less people want a car for a higher price), by creating new supply (providing an incentive for new drivers to hit the roads), or by shifting supply (drivers) to areas of higher demand." It moves current drivers from one side of town to the other. It does not put new drivers on the road. It can't because the prices change every 3-5 minutes."

    Read more of this story at Slashdot.

  • Star Wars Battlefront Game Trailer Is So Realistic It Looks Like Movie Footage
    2015-04-19T16:13:00+00:00
    MojoKid writes It has been a tremendous week for Star Wars fans. First we got to see Han Solo and Chewbacca make an emotional reappearance in the newest Star Wars: The Force Awakens trailer (the second official trailer Disney has put out). Now, Electronic Arts is treating us to a visual smorgasbord of cinema-quality footage showing the forthcoming Star Wars Battlefront game. Battlefront will support to up 40 players divided between the Rebel Alliance and Galactic Empire, all shooting it out and playing with some of the coolest Star Wars vehicles and weapons around. We're talking jetpacks, AT-AT war machines, AT-STs, TIE Fighters, X-wings, and more. Though the trailer allegedly shows actually "game engine footage," it's questionable whether or not it's actual gameplay or just pre-rendered cut scenes from the game engine. Either way, it's still pretty impressive.

    Read more of this story at Slashdot.

  • Utilities Battle Homeowners Over Solar Power
    2015-04-19T15:18:00+00:00
    HughPickens.com writes Diane Cardwell reports in the NYT that many utilities are trying desperately to stem the rise of solar power, either by reducing incentives, adding steep fees or effectively pushing home solar companies out of the market. The economic threat has electric companies on edge. Over all, demand for electricity is softening while home solar is rapidly spreading across the country. There are now about 600,000 installed systems, and the number is expected to reach 3.3 million by 2020, according to the Solar Energy Industries Association. In Hawaii, the current battle began in 2013, when Hawaiian Electric started barring installations of residential solar systems in certain areas. It was an abrupt move — a panicked one, critics say — made after the utility became alarmed by the technical and financial challenges of all those homes suddenly making their own electricity. "Hawaii is a postcard from the future," says Adam Browning, executive director of Vote Solar, a policy and advocacy group based in California. But utilities say that solar-generated electricity flowing out of houses and into a power grid designed to carry it in the other direction has caused unanticipated voltage fluctuations that can overload circuits, burn lines and lead to brownouts or blackouts. "At every different moment, we have to make sure that the amount of power we generate is equal to the amount of energy being used, and if we don't keep that balance things go unstable," says Colton Ching, vice president for energy delivery at Hawaiian Electric, pointing to the illuminated graphs and diagrams tracking energy production from wind and solar farms, as well as coal-fueled generators in the utility's main control room. But the rooftop systems are "essentially invisible to us," says Ching, "because they sit behind a customer's meter and we don't have a means to directly measure them." The utility wants to cut roughly in half the amount it pays customers for solar electricity they send back to the grid. "Hawaii's case is not isolated," says Massoud Amin. "When we push year-on-year 30 to 40 percent growth in this market, with the number of installations doubling, quickly — every two years or so — there's going to be problems."

    Read more of this story at Slashdot.

  • DIA Polygraph Countermeasure Case Files Leaked
    2015-04-19T14:22:00+00:00
    George Maschke writes AntiPolygraph.org (of which I am a co-founder) has published a set of leaked Defense Intelligence Agency polygraph countermeasure case files along with a case-by-case analysis. The case files, which include polygraph charts and the exact questions used, suggest that the only people being "caught" trying to beat the polygraph are those using crude, unsophisticated methods that anyone who actually understood polygraph procedure and effective countermeasures (like, say, a real spy, saboteur, or terrorist) would ever use. AntiPolygraph.org has previously published polygraph community training materials on countermeasures that indicate they lack the ability to detect countermeasures like those described in our free book, The Lie Behind the Lie Detector (PDF) or in former police polygraph examiner Doug Williams' manual, How to Sting the Polygraph . Williams, who was indicted last year after teaching undercover federal agents how to pass a polygraph, is scheduled to stand trial on May 12 in Oklahoma City.

    Read more of this story at Slashdot.

  • Does Lack of FM Support On Phones Increase Your Chances of Dying In a Disaster?
    2015-04-19T12:27:00+00:00
    theodp writes You may not know it," reports NPR's Emma Bowman, "but most of today's smartphones have FM radios inside of them. But the FM chip is not activated on two-thirds of devices. That's because mobile makers have the FM capability switched off. The National Association of Broadcasters has been asking mobile makers to change this. But the mobile industry, which profits from selling data to smartphone users, says that with the consumer's move toward mobile streaming apps, the demand for radio simply isn't there." But FEMA Administrator Craig Fugate says radio-enabled smartphones could sure come in handy during times of emergency. So, is it irresponsible not to activate the FM chips? And should it's-the-app-way-or-the-highway Apple follow Microsoft's lead and make no-static-at-all FM available on iPhones?

    Read more of this story at Slashdot.

  • US Military To Recruit Civilian Cybersecurity Experts
    2015-04-19T09:22:00+00:00
    An anonymous reader writes The U.S. Army is to create a new cybersecurity division, Cyber Branch 17, and is also considering launching a cyber career track for civilians, according to an announcement made this week by Lt. Gen. Edward C. Cardon. Cardon, who currently heads the U.S. Army's cyber command, ARCYBER, spoke to the Senate Armed Services subcommittee on Tuesday about the growing threats and capabilities used in cyber warfare. He argued that creating a cyber career management field for civilians would result in an easier recruitment process, as opposed to recruiting internally and trying to retain the talent, he said. Cardon maintains that recruiting and retaining talent in the field is often challenging, given internal employment constraints surrounding compensation and slow hiring processes.

    Read more of this story at Slashdot.

  • FBI Overstated Forensic Hair Matches In Nearly All Trials Before 2000
    2015-04-19T06:29:00+00:00
    schwit1 writes The Justice Department and FBI have formally acknowledged that nearly every examiner in an elite FBI forensic unit gave flawed testimony in almost all trials in which they offered evidence against criminal defendants over more than a two-decade period before 2000. Of 28 examiners with the FBI Laboratory's microscopic hair comparison unit, 26 overstated forensic matches in ways that favored prosecutors in more than 95 percent of the 268 trials reviewed so far, according to the National Association of Criminal Defense Lawyers (NACDL) and the Innocence Project, which are assisting the government with the country's largest post-conviction review of questioned forensic evidence. The cases include those of 32 defendants sentenced to death. Of those, 14 have been executed or died in prison, the groups said under an agreement with the government to release results after the review of the first 200 convictions.

    Read more of this story at Slashdot.

  • Google To Propose QUIC As IETF Standard
    2015-04-19T03:33:00+00:00
    As reported by TechCrunch, "Google says it plans to propose HTTP2-over-QUIC to the IETF as a new Internet standard in the future," having disclosed a few days ago that about half of the traffic from Chrome browsers is using QUIC already. From the article: The name "QUIC" stands for Quick UDP Internet Connection. UDP's (and QUIC's) counterpart in the protocol world is basically TCP (which in combination with the Internet Protocol (IP) makes up the core communication language of the Internet). UDP is significantly more lightweight than TCP, but in return, it features far fewer error correction services than TCP. ... That's why UDP is great for gaming services. For these services, you want low overhead to reduce latency and if the server didn't receive your latest mouse movement, there's no need to spend a second or two to fix that because the action has already moved on. You wouldn't want to use it to request a website, though, because you couldn't guarantee that all the data would make it. With QUIC, Google aims to combine some of the best features of UDP and TCP with modern security tools.

    Read more of this story at Slashdot.

  • Joseph Goebbels' Estate Sues Publisher Over Diary Excerpt Royalties
    2015-04-19T00:23:00+00:00
    wabrandsma writes with this from The Guardian: The estate of Joseph Goebbels, Adolf Hitler's minister of propaganda, is taking legal action against the publisher Random House over a new biography, claiming payment for the use of extracts from his diaries. Peter Longerich's biography of Goebbels is to be published in May (Random House/ Siedler). Longerich, who is the professor at Royal Holloway's Holocaust Research Centre, maintains this case has important censorship implications. 'If you accept that a private person controls the rights to Goebbels' diaries, then – theoretically – you give this person the right to control research,' he said.

    Read more of this story at Slashdot.

  • DOJ Could Nix Comcast-Time Warner Merger
    2015-04-18T22:42:00+00:00
    jriding (1076733) writes The Comcast-Time Warner Cable merger has been in the works for so long, it's starting to feel like the impending monopolistic telecom Frankenbaby was inevitable. But the Justice Department may kibosh the deal for violating antitrust laws, according to a report from Bloomberg.

    Read more of this story at Slashdot.

  • Norway Will Switch Off FM Radio In 2017
    2015-04-18T21:25:00+00:00
    New submitter titten writes The Norwegian Ministry of Culture has announced that the transition to DAB will be completed in 2017. This means that Norway, as the first country in the world to do so, has decided to switch off the FM network. Norway began the transition to DAB in 1995. In recent years two national and several local DAB-networks has been established. 56 per cent of radio listeners use digital radio every day. 55 per cent of households have at least one DAB radio, according to Digitalradio survey by TNS Gallup, continuously measuring the Norwegian`s digital radio habits.

    Read more of this story at Slashdot.

  • Ask Slashdot: What Features Would You Like In a Search Engine?
    2015-04-18T20:32:00+00:00
    New submitter nicolas.slusarenko writes Nowadays, there is one dominant search engine in the world among few alternatives. I have the impression that the majority of users think that it is the best possible service that could be made. I am sure that we could have a better search engine. During my spare time I been developing Trokam, an online search engine. I am building this service with the features that I would like to find in a service: respectful of user rights, ad-free, built upon open source software, and with auditable results. Well, those are mine. What features would you like in a search engine?

    Read more of this story at Slashdot.

  • The Upsides of a Surveillance Society
    2015-04-18T19:27:00+00:00
    theodp writes Citing the comeuppance of ESPN reporter Britt McHenry, who was suspended from her job after her filmed ad-hominem attack on a person McHenry deemed to be beneath her in terms of appearance, education, wealth, class, status went viral, The Atlantic's Megan Garber writes that one silver lining of the omnipresence of cameras it that the possibility of exposure can also encourage us to be a little kinder to each other. "Terrible behavior," Garber writes, "whether cruel or violent or something in between, has a greater possibility than it ever has before of being exposed. Just as Uber tracks ratings for both its drivers and its users, and just as Yelp can be a source of shaming for businesses and customers alike, technology at large has afforded a reciprocity between people who, in a previous era, would have occupied different places on the spectrum of power. Which can, again, be a bad thing — but which can also, in McHenry's case, be an extremely beneficial one. It's good that her behavior has been exposed. It's good that her story going viral might discourage similar behavior from other people. It's good that she has publicly promised 'to learn from this mistake.'"

    Read more of this story at Slashdot.

  • Dutch Prosecutors Launch Criminal Investigation Against Uber For Flouting Ban
    2015-04-18T18:25:00+00:00
    An anonymous reader writes Dutch prosecutors have announced that they are prosecuting taxi-hailing giant Uber for continuing to disregard last December's ban on the company offering its unlicensed UberPOP service in the Netherlands. The statement declares 'The company Uber is now a suspect...This means a preliminary examination will be started to collect evidence that Uber is providing illegal transportation on a commercial basis,'. Dutch police presented evidence to the prosecutors of UberPOP drivers in Amsterdam ignoring the ban, and at the time of writing the UberPOP service is still available via Uber's Amsterdam website [https://www.uber.com/cities/amsterdam]. Though Uber inspires new litigation on a weekly basis in the territories in which it is seeking to consolidate its services, this is the first time it has been the subject of a criminal prosecution.

    Read more of this story at Slashdot.

  • Resistance To Antibiotics Found In Isolated Amazonian Tribe
    2015-04-18T17:29:00+00:00
    sciencehabit writes When scientists first made contact with an isolated village of Yanomami hunter-gatherers in the remote mountains of the Amazon jungle of Venezuela in 2009, they marveled at the chance to study the health of people who had never been exposed to Western medicine or diets. But much to their surprise, these Yanomami's gut bacteria have already evolved a diverse array of antibiotic-resistance genes, according to a new study, even though these mountain people had never ingested antibiotics or animals raised with drugs. The find suggests that microbes have long evolved the capability to fight toxins, including antibiotics, and that preventing drug resistance may be harder than scientists thought.

    Read more of this story at Slashdot.

 

dept@math.duke.edu
ph: 919.660.2800
fax: 919.660.2821

Mathematics Department
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