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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
Attitude is half reality.
    --- me?
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 :-)

  • Astronomers Discover 83 Supermassive Black Holes at the Edge of the Universe
    2019-03-18T11:34:00+00:00
    "A team of international astronomers have been hunting for ancient, supermassive black holes -- and they've hit the motherlode, discovering 83 previously unknown quasars," reports CNET: The Japanese team turned the ultra-powerful "Hyper Suprime-Cam", mounted to the Subaru Telescope in Hawaii, toward the cosmos' darkest corners, surveying the sky over a period of five years. By studying the snapshots, they've been able to pick potential quasar candidates out of the dark. Notably, their method of probing populations of supermassive black holes that are similar in size to the ones we see in today's universe, has given us a window into their origins. After identifying 83 potential candidates, the team used a suite of international telescopes to confirm their findings. The quasars they've plucked out are from the very early universe, about 13 billion light years away. Practically, that means the researchers are looking into the past, at objects form less than a billion years after the Big Bang. "It is remarkable that such massive dense objects were able to form so soon after the Big Bang," said Michael Strauss, who co-authored the paper, in a press release. Scientists aren't sure how black holes formed in the early universe, so being able to detect them this far back in time provides new avenues of exploration.

    Read more of this story at Slashdot.

  • Wells Fargo Sued By 63-Year-Old Pastor They Wrongfully Accused of Forging Checks
    2019-03-18T07:34:00+00:00
    Wells Fargo has been hit with a lawsuit from a 63-year-old pastor at the United Methodist Church of Parsippany. Wells Fargo sent his ATM photos to the police, which he says led to false arrest, malicious prosecution -- and humiliation. NJ.com reports: In the lawsuit filed Thursday in Morris County Superior Court, attorneys for the 63-year-old pastor sought unspecified damages against Wells Fargo, which has come under fire over a series of scandals in recent years. Also named were the State Police detectives who originally brought the charges against him last year after bank security officials allegedly mistakenly identified a photo of Edwards taken at an ATM machine as a suspect in a series of fraudulent check deposits.... In the lawsuit, Edwards' attorney wrote that Wells Fargo notified the State Police when it discovered the bogus transactions, and the bank was asked to provide any still photos or video images taken from the ATM at Parsippany where some of the checks were deposited and later cashed out. The bank sent photos of Edwards, who had made his own deposit of checks at the same ATM the very same day, according to the complaint... The pastor said he first discovered he was the focus of a criminal investigation last year after a parishioner texted him a State Police Facebook posting requesting the public's help identifying a man suspected of depositing fraudulent checks at an ATM... In an interview, Edwards said after seeing the post, he called the detectives and shared a copy of his banking transactions to show he had not deposited the fraudulent checks. "I thought it would clear things up," he said. "They said all their information was from Wells Fargo..." Last September, Edwards said he was asked to come down to the State Police station in Holmdel. After he got there, he said he was shocked to find out he was being arrested and charged with third degree forgery. When he protested and said somebody made an error, he said one of the investigators asked him if the case did go to trial, who would the jury believe -- a bank security expert or him? "They fingerprinted me. Took my mug shot and gave me a court date," he said. The case fell apart, but the 63-year-old pastor says he never received an apology from the police, or from Wells Fargo. "The carelessness of both Wells Fargo and the State Police is kind of appalling, and I wonder what happens to somebody who might not have the resources to defend themselves," the pastor told NJ.com. "I told them yes that was my picture and yes I was in the bank that day. That's all they needed to arrest me." A spokesman for Wells Fargo told the reporter they'd be unable to comment "since this is a pending legal matter." But the story was submitted to Slashdot by someone claiming to be pastor Jeff Edwards. "Wells Fargo carelessly provided ATM pictures [of] me to the state police in a fraudulent check investigation that led to my arrest," reads the original submission. "The case was dismissed when it was demonstrated that Wells Fargo had been grossly irresponsible."

    Read more of this story at Slashdot.

  • BBC Visits 'Hated and Hunted' Ransomware Expert
    2019-03-18T03:34:00+00:00
    In "Hated and hunted," a BBC reporter describes visiting a ransomware expert "who has devoted himself, at huge personal cost, to helping victims of ransomware around the world." They hate him so much that they leave him angry threats buried deep inside the code of their own viruses... "I was shocked but I also felt a real sense of pride," says Fabian. "Almost like, a little bit cocky. I'm not going to lie, yeah, it was nice...." He works remotely for a cyber security company, often sitting for hours at a time working with colleagues in different countries. When he's "in the zone", the outside world becomes even less important and his entire existence focuses on the code on his screen. He once woke up with keyboard imprints all over his face after falling asleep during a 35-hour session. All of this to create anti-ransomware programs that he and his company usually give away free. Victims simply download the tools he makes for each virus, follow the instructions and get their files back... According to research from Emsisoft, the cyber security company Fabian works for, a computer is attacked every two seconds. Their network has managed to prevent 2,584,105 infections in the past 60 days -- and that's just one anti-virus firm of dozens around the world.... "It's pretty much an arms race," says Fabian. "They release a new ransomware virus, I find a flaw in its code and build the decryption tool to reverse it so people can get their files back. Then the criminals release a new version which they hope I can't break... It escalates with them getting more and more angry with me...." Fabian accepts that moving around and restricting his life and circle of friends is just a part of the sacrifice for his hobby-turned-profession... He earns a very good salary but looking around his home and at his life it's hard to see how he spends it. He estimates that he's "upset or angered" 100 different ransomware gangs (based on his analysis of the Bitcoin wallets where they collect their ransoms.) One group had collected about $250,000 (£191,000) in three months -- until Fabian created a countering anti-ransomware program -- which is one reason he carefully hids his identity. "I know how much money they make and it would be literally nothing for them to drop 10 or 20,000 for like some Russian dude to turn up to my house and beat the living hell out of me."

    Read more of this story at Slashdot.

  • Vaccines Can Help Fight the Rise of Drug-Resistant Microbes
    2019-03-18T02:34:00+00:00
    An anonymous reader quotes the Harvard School of Public Health: Drug-resistant strains of gonorrhea, salmonella, Escherichia coli (E. coli) and many other disease-causing agents are flourishing around the world, and the consequences are disastrous -- at least 700,000 people die globally as a result of antimicrobial resistance (AMR) annually, according to a 2016 review on antimicrobial resistance commissioned by former UK Prime Minister David Cameron. It's a perilous situation, but several new studies from researchers at Harvard T.H. Chan School of Public Health indicate that an important tool in the fight against AMR already exists: vaccines. The Proceedings of the National Academy of Sciences recently devoted a special feature section to examine the role vaccines can play in stemming the tide of antimicrobial resistance. In general terms, vaccinations can help lessen the burden in two ways: First, they can protect against the direct transmission of drug-resistant infections. Second, they can lessen the chances of someone getting sick, which in turn reduces the likelihood that he or she will be prescribed antibiotics or other medications. The fewer medications someone takes, the less likely it is that microbes will evolve resistance to the drugs.

    Read more of this story at Slashdot.

  • Bacteria Discovered In Irish Soil Kills Four Drug-Resistant Superbugs
    2019-03-18T01:34:00+00:00
    NBC News reports on how microbiologist Gerry Quinn "followed up on some folklore his family had passed on to him." Old timers insisted that the dirt in the vicinity of a nearly 1,500-year-old church in County Fermanagh in Northern Ireland, an area once occupied by the Druids, had almost miraculous curative powers.... "Here in the western fringes of Ireland there is still a tradition of having this folk cure," Quinn told NBC News. "We can look at it and see maybe it's just superstition -- or we can actually investigate and ask, 'is there anything in the soil that produces antibiotics...?'" Once Quinn and his team decided to focus on the Irish soil, they narrowed their search to a specific type of bacteria, called Streptomyces, because other strains of this bacteria have led to the development of 75 percent of existing antibiotics, Quinn said. The bacteria was discovered by a team based at Swansea University Medical School, made up of researchers from Wales, Brazil, Iraq and Northern Ireland. The researchers first tried the newly discovered strain of Streptomyces on some garden variety bacteria. In their petri dish experiment, "it knocked them out," Quinn said. "Then we thought we'd take it one step further and find some multi-resistant organisms." The bacteria in the experiment killed four out of the top six organisms that are resistant to antibiotics, including MRSA. "It's quite surprising," said Quinn... "The lesson is, some of the cures are right underneath your feet." Vaughn Cooper, an evolutionary geneticist/microbiologist at the University of Pittsburgh's School of Medicine, tells NBC that more research is needed before this yields a super-antibiotic -- but "it's a cool discovery." The World Health Organization has named antibiotic resistance as one of 2019's ten top public health threats.

    Read more of this story at Slashdot.

  • Nevada Lawmakers Want Police To Scan Cellphones After Car Crashes
    2019-03-17T23:34:00+00:00
    An anonymous reader quotes the Associated Press: Most states ban texting behind the wheel, but a legislative proposal could make Nevada one of the first states to allow police to use a contentious technology to find out if a person was using a cellphone during a car crash... If the Nevada measure passes, it would allow police to use a device known as the "textalyzer," which connects to a cellphone and looks for user activity, such as opening a Facebook messenger call screen. It is made by Israel-based company Cellebrite, which says the technology does not access or store personal content. It has not been tested in the field and is not being used by any law enforcement agencies. The company said the device could be tested in the field if the Nevada legislation passes... Opponents air concerns that the measure violates the Fourth Amendment, which protects against unreasonable search and seizure. Jay Stanley, a senior policy analyst at the American Civil Liberties Union, also raised questions over how the software will work and if it will be open sourced so the public can ensure it doesn't access personal content... Law enforcement officials argue that distracted driving is underreported and that weak punishments do little to stop drivers from texting, scrolling or otherwise using their phones. Adding to the problem, they say there is no consistent police practice that holds those drivers accountable for traffic crashes, unlike drunken driving.

    Read more of this story at Slashdot.

  • Before Google+ Shuts Down, The Internet Archive Will Preserve Its Posts
    2019-03-17T22:34:00+00:00
    Google+ "was an Internet-based social network. It was almost 8 years old," reports KilledByGoogle.com, which bills itself as "The Google Graveyard: A list of dead products Google has killed and laid to rest in the Google Cemetery." But before Google+ closes for good in April, its posts are being preserved by Internet Archive and the ArchiveTeam, reports the Verge: In a post on Reddit, the sites announced that they had begun their efforts to archive the posts using scripts to capture and back up the data in an effort to preserve it. The teams say that their efforts will only encompass posts that are currently available to the public: they won't be able to back up posts that are marked private or deleted... They also note that they won't be able to capture everything: comment threads have a limit of 500 comments, "but only presents a subset of these as static HTML. It's not clear that long discussion threads will be preserved." They also say that images and video won't be preserved at full resolution... They also urge people who don't want their content to be archived to delete their accounts, and pointed to a procedure to request the removal of specific content. A bit of history: Linus Torvalds launched a Google+ page in 2017 called "Gadget Reviews" -- where he made exactly six posts.

    Read more of this story at Slashdot.

  • Why Robo-Calls Can't Be Stopped
    2019-03-17T21:34:00+00:00
    "When your phone rings, there's about a 50 percent chance it's a spam robo-call," reports the Washington Post. Now a computer science professor who's researched robo-call technologies reveals the economics behind automatically dialing phone numbers "either randomly, or from massive databases compiled from automated Web searches, leaked databases of personal information and marketing data." It doesn't matter whether you've signed up with the federal Do Not Call Registry, although companies that call numbers on the list are supposed to be subject to large fines. The robo-callers ignore the list, and evade penalties because they can mask the true origins of their calls.... Each call costs a fraction of a cent -- and a successful robo-call scam can net millions of dollars. That more than pays for all the calls people ignored or hung up on, and provides cash for the next round. Casting an enormous net at low cost lets these scammers find a few gullible victims who can fund the whole operation... Partly that's because their costs are low. Most phone calls are made and connected via the Internet, so robo-call companies can make tens of thousands, or even millions, of calls very cheaply. Many of the illegal robo-calls targeting the United States probably come from overseas -- which used to be extremely expensive but now is far cheaper... Meanwhile, the Federal Communications Commission has been asking U.S. phone companies to filter calls and police their own systems to keep out robo-calls. It hasn't worked, mainly because it's too costly and technically difficult for phone companies to do that. It's hard to detect fake Caller ID information, and wrongly blocking a legitimate call could cause them legal problems. The professor's article suggests guarding your phone number like you guard your credit card numbers. "Don't give your phone number to strangers, businesses or websites unless it's absolutely necessary." "Of course, your phone number may already be widely known and available, either from telephone directories or websites, or just because you've had it for many years. In that case, you probably can't stop getting robo-calls."

    Read more of this story at Slashdot.

  • Are We Getting Close To Flying Taxis?
    2019-03-17T20:34:00+00:00
    An anonymous reader quotes a report from public news station KNPR about how close weare flying taxi services: The dream of flying cars is as at least as old as the automobile itself. Bell, which makes attack helicopters for the U.S. Navy, is working on this new project with another high-profile partner, Uber. The prototype, the Bell Nexus, was unveiled earlier this year. Boeing and Airbus also have prototypes of these flying cars in the works. Uber has become the face of the aerial mobility movement as it has the most public campaign touting its work so far. Elon Musk says he'll get us to Mars. Uber says it'll get a millennial from San Francisco to San Jose in 15 minutes flat (instead of the two-hour slog in morning traffic). And its timeline for this flying taxi that does not yet exist is 2023... NASA is another Uber partner. While Jaiwon Shin, NASA's associate administrator for the Aeronautics Research Mission Directorate, thinks Uber is being a little bullish -- he'd put the timeline further out, to the mid-2020s -- Shin says it's close. "Convergence of many different technologies are maturing to the level that now aviation can benefit to put these things together," he said. The batteries that power electric cars can evolve further, to power flight. Companies can stockpile and pool data, and build artificial intelligence to take over air traffic control, managing the thousands of drones and taxis in the air. And Uber, his partner, is really well-connected. While fighting the legacy taxi industry, Uber made so many government and lobbyist contacts, that that Rolodex can help grease the wheels -- or wings. "While no flying taxi exists yet, Uber has dared to estimate the 'near-term' cost of that San Francisco to San Jose trip: $43," the article reports -- suggesting that could create a new division in society. "With flying cars, the haves can escape to the air and leave the have-nots forgotten in their potholes."

    Read more of this story at Slashdot.

  • Texas Lawmakers Want To Stop Tesla From Fixing Its Own Cars
    2019-03-17T19:34:00+00:00
    In Texas the local car dealer lobby has blocked Tesla from selling its cars directly to customers. They're using old laws meant to prevent car manufacturers from competing with their own local dealers -- but Tesla never had any local dealers! And according to Electrek, it gets worse... Despite this issue, Texans have bought thousands of Tesla vehicles, which the automaker delivers from other states to comply with the law. Tesla has been able to service those vehicles through its own service centers, which are not subject to those same direct-sale rules, but now dealers are even going after Tesla's right to service its cars. Quartz offers some additional coverage: At issue is a battle over money. Car dealers derive much of their revenue from selling and (especially) servicing vehicles. Tesla's direct-to-customer sales and service stations are a threat to that business model since they cut dealers out of the transaction.

    Read more of this story at Slashdot.

  • To Avoid Demonetization, YouTube and Twitch Streamers Sing Badly Over Copyrighted Songs
    2019-03-17T18:34:00+00:00
    To avoid copyright claims, "YouTube creators and Twitch streamers have been performing terrible a capella covers of popular songs," reports the Verge: React videos are a huge part of YouTube's current culture; people lift popular movie trailers and film their reactions to what's happening on-screen. These videos are typically monetized... In recent months, YouTube creators have run into copyright issues while making TikTok reaction videos, where they collect cringey TikTok clips and either react or provide commentary on them. [T]hose TikTok videos contain music from artists signed to labels like Sony and Warner, and those labels will issue copyright claims, preventing creators from monetizing their videos... TikTok videos include less than 10 seconds of music, yet that can still be enough to receive a copyright claim -- on TikTok itself, the music is all licensed from the labels... To work around that, creators like Danny Gonzalez and Kurtis Conner have started replacing the music with their own singing. Gonzalez and Conner half-heartedly sing songs like Linkin Park's "In The End" and Imagine Dragons' "Believer" while the corresponding TikTok video plays on screen... It's a little painful to hear, but ultimately a very fun loophole in the copyright system that YouTube has to enforce... The hope is that major labels like Sony Music or Warner Music Group can't claim copyright infringement, or at least that the singing won't trigger YouTube's automated system for finding copyrighted content.

    Read more of this story at Slashdot.

  • 'Facebook, Axios And NBC Paid This Guy To Whitewash Wikipedia Pages'
    2019-03-17T17:34:00+00:00
    The Huffington Post ran a bombshell report this week on one of a handful of people who have "figured out how to manipulate Wikipedia's supposedly neutral system to turn a profit." They're describing Ed Sussman, a former head of digital for Fast Company and Inc.com who's now paid to do damage control by relentlessly lobbying for changes to Wikipedia pages. "In just the past few years, companies including Axios, NBC, Nextdoor and Facebook's PR firm have all paid him to manipulate public perception using a tool most people would never think to check. And it almost always works." Spin reports: The benefit of hiring Sussman, aside from insulating talking heads from the humiliation of being found to have edited their own pages, is that he applies the exacting and annoying vigor of an attorney to Wikipedia's stringent editing rules. Further, because his opponents in these arguments are not opposing lawyers but instead Wikipedia's unpaid editors, he's really effective. From HuffPost: "Sussman's main strategy for convincing editors to make the changes his clients want is to cite as many tangentially related rules as possible (he is, after all, a lawyer). When that doesn't work, though, his refusal to ever back down usually will. He often replies to nearly every single bit of pushback with walls of text arguing his case. Trying to get through even a fraction of it is exhausting, and because Wikipedia editors are unpaid, there's little motivation to continue dealing with Sussman's arguments. So he usually gets his way." NBC and Axios confirmed that they hired Sussman, and an Axios spokesperson told HuffPost that the site "hired him to correct factual inaccuracies." The spokesperson added "pretty sure lots of people do this," which may or may not be true. Sussman's web site argues he's addressing "inaccurate or misleading information...potentially creating severe business problems for its subject," bragging in his FAQ that when he's finished, "the article looks exactly the same" to an outsider -- and that his success rate is 100%.

    Read more of this story at Slashdot.

  • Some Companies Choose Microsoft's Cloud Service Because They're Afraid of Amazon
    2019-03-17T16:34:00+00:00
    "In the cloud wars, Microsoft has been able to win big business from retailers, largely because companies like Walmart, Kroger, Gap and Target are opting not to write big checks to rival Amazon," reports CNBC: The more Amazon grows, the more that calculation could start working its way into other industries -- like automotive. In a recent interview with CNBC, Volkswagen's Heiko Huttel, who runs the company's connected car division, said the carmaker chose Microsoft Azure late last year for its "Automotive Cloud" project after considering Amazon Web Services... "If I take a look at all the competitors out there, you see they have capabilities in disrupting you at the customer interface," Hüttel said. "Then you have to carefully choose who is really getting down into the car, where you open up a lot of data to these people, and then you have to carefully choose with whom you are doing business." Microsoft likes to tout the merits of its cloud technology, but the company is fully aware that taking on AWS, which has a commanding lead in the cloud infrastructure market, isn't just about offering the best services... Microsoft doesn't break out Azure revenue, but analysts at Morgan Stanley estimate that it accounted for almost 10 percent of sales in the latest quarter.

    Read more of this story at Slashdot.

  • Sealed Cache of Moon Rocks To Be Opened By NASA
    2019-03-17T15:34:00+00:00
    "Scientists are hoping to unlock some of the universe's mysteries through 50-year-old moon rocks," reports the New York Daily News -- specifically, three samples that spent that half century sealed in airtight canisters. One Apollo 18 sample from 1972 contains 1.8 pounds of a vacuum-sealed lunar core that is a stratified layer of rock that will be studied by six research teams. About 842 pounds of lunar rocks and soil have been brought back to Earth over six missions. Although a great deal of it has found its way to science labs, technological breakthroughs should allow for a more thorough comprehension of the satellite's chemical and geological composition... "When the previous generations did Apollo, they knew the technology they had in that day was not the technology we would have in this day," said NASA Administrator Jim Bridenstine. "So they made a determination that they would preserve samples. ⦠I'd like to thank, if it's OK, the Apollo generation, for preserving these samples, so that our generation could have this opportunity." An anonymous Slashdot reader writes, "That's remarkable considering how often moon rocks were misplaced over the years."

    Read more of this story at Slashdot.

  • Massive Study Finds Apple Watch Can Detect Undiagnosed Heart Rhythm Problems
    2019-03-17T14:34:00+00:00
    An anonymous reader quotes Engadget: Researchers from Stanford University's School of Medicine presented results from a giant study sponsored by Apple Inc. that showed the Apple Watch can sometimes spot patients with undiagnosed heart-rhythm problems, without producing large numbers of false alarms. The Apple-sponsored trial enrolled 419,297 people and was one of the largest heart-screening studies ever. The study, details of which are being presented today at the American College of Cardiology conference in New Orleans, used the watch's sensors to detect possible atrial fibrillation... People who have atrial fibrillation are at risk of blood clots and strokes. In the U.S., it causes 750,000 hospitalizations a year and contributes to 130,000 deaths, according to the Centers for Disease Control and Prevention. Because it doesn't always produce outward symptoms, it can go undiagnosed. According to results presented Saturday, about 0.5 percent of patients in the study -- or almost 2,100 people -- received notices from their watch indicating that they might have a heart-rhythm problem. That relatively low number showed that the technology wasn't inundating people with worrisome alerts. People receiving a notification were asked to then wear an ECG (electrocardiography) patch, according to the Verge, adding that Stanford reports "84 percent of the time, participants who received irregular pulse notifications were found to be in atrial fibrillation at the time of the notification." The dean of Stanford's medical school says the study "opens the door to further research into wearable technologies and how they might be used to prevent disease before it strikes."

    Read more of this story at Slashdot.

 

dept@math.duke.edu
ph: 919.660.2800
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Mathematics Department
Duke University, Box 90320
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