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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 :-)

  • The Case that Bitcoin Is a Bubble
    2017-12-11T17:20:00+00:00
    An anonymous reader shares an excerpt from the Economist: It seems that every day, Bitcoin seems to hit a new high. But the reported price can move up and down by $1,000 or so within a few hours. This might have made it a great investment for those who got in at the right price and are nimble enough to get out in time. But it doesn't make it a useful means of exchange (Editor's note: the link could be paywalled; alternative source). When the price is rising fast, those who use bitcoin will be reluctant to part with it; when the price falls, those who sell goods will be reluctant to accept it.

    Read more of this story at Slashdot.

  • Bitcoin Futures Surge In First Day Of Trading
    2017-12-11T16:41:00+00:00
    On their first day of trading, bitcoin futures surged past $18,000, adding to a streak for the digital currency that began the year at just $1,000 and has nearly tripled in value over the past month alone. From a report: Reuters reports that bitcoin futures, traded through the Chicago Board Options Exchange (CBOE), saw January contracts, which opened at $15,460 in New York on Sunday evening, leap to a high of $17,170 during Asian hours. Trading, which began at 6 p.m. ET (5 p.m. CT), was so intense that halts designed to cool volatility were triggered twice on the CBOE. The halts are "not surprising based on the volatility of the underlying [asset]. The futures are behaving as expected and designed," Tom Lehrkinder, senior analyst at consulting firm Tabb Group, was quoted by CNBC as saying.

    Read more of this story at Slashdot.

  • Former Facebook Exec Says Social Media is Ripping Apart Society
    2017-12-11T16:00:00+00:00
    An anonymous reader shares a report on The Verge: Another former Facebook executive has spoken out about the harm the social network is doing to civil society around the world. Chamath Palihapitiya, who joined Facebook in 2007 and became its vice president for user growth, said he feels "tremendous guilt" about the company he helped make. "I think we have created tools that are ripping apart the social fabric of how society works," he told an audience at Stanford Graduate School of Business, before recommending people take a âoehard breakâ from social media. Palihapitiya's criticisms were aimed not only at Facebook, but the wider online ecosystem. "The short-term, dopamine-driven feedback loops we've created are destroying how society works," he said, referring to online interactions driven by "hearts, likes, thumbs-up." "No civil discourse, no cooperation; misinformation, mistruth. And it's not an American problem -- this is not about Russians ads. This is a global problem." Also read: Sean Parker Unloads on Facebook 'Exploiting' Human Psychology

    Read more of this story at Slashdot.

  • German Intelligence Warns of Increased Chinese Cyberspying
    2017-12-11T15:20:00+00:00
    The head of Germany's domestic intelligence agency has warned that China allegedly is using social networks to try to cultivate lawmakers and other officials as sources. From a report: Hans-Georg Maassen said his agency, known by its German acronym BfV, believes more than 10,000 Germans have been targeted by Chinese intelligence agents posing as consultants, headhunters or researchers, primarily on the social networking site LinkedIn. "This is a broad-based attempt to infiltrate in particular parliaments, ministries and government agencies," Maassen said.

    Read more of this story at Slashdot.

  • Fired Tech Workers Turn To Chatbots for Counseling
    2017-12-11T14:40:00+00:00
    An anonymous reader shares a Bloomberg report: For months Lovkesh Joshi was quietly terrified of losing his job as a manager at a top Indian tech services company. Joshi didn't want to burden his wife or friends so he turned to a chatbot therapist called Wysa. Powered by AI, the app promises to be "loyal, supportive and very private," and encourages users to divulge their feelings about a recent major event or big change in their lives. "I could open up and talk," says the 41-year-old father of two school-age children, who says his conversations with the bot flowed naturally. "I felt heard and understood." Joshi moved to a large rival outsourcer two months ago. The upheaval in India's $154 billion tech outsourcing industry has prompted thousands of Indians to seek solace in online therapy services. People accustomed to holding down prestigious jobs and pulling in handsome salaries are losing out to automation, a shift away from long-term legacy contracts and curbs on U.S. work visas. McKinsey & Co says almost half of the four million people working in India's IT services industry will become "irrelevant" in the next three to four years. Indians, like people the world over, tend to hide their mental anguish for fear of being stigmatized. That's why many are embracing the convenience, anonymity and affordability of online counseling startups, most of which use human therapists.

    Read more of this story at Slashdot.

  • HP Laptops Found To Have Hidden Keylogger
    2017-12-11T14:00:00+00:00
    Hidden software that can record every letter typed on a computer keyboard has been discovered pre-installed on hundreds of HP laptop models, BBC reported on Monday citing the findings of a security researcher. From the report: Security researcher Michael Myng found the keylogging code in software drivers preinstalled on HP laptops to make the keyboard work. HP said more than 460 models of laptop were affected by the "potential security vulnerability." It has issued a software patch for its customers to remove the keylogger. The issue affects laptops in the EliteBook, ProBook, Pavilion and Envy ranges, among others. HP has issued a full list of affected devices, dating back to 2012. Mr Myng discovered the keylogger while inspecting Synaptics Touchpad software, to figure out how to control the keyboard backlight on an HP laptop. He said the keylogger was disabled by default, but an attacker with access to the computer could have enabled it to record what a user was typing. According to HP, it was originally built into the Synaptics software to help debug errors. It acknowledged that could lead to "loss of confidentiality" but it said neither Synaptics nor HP had access to customer data as a result of the flaw.

    Read more of this story at Slashdot.

  • Ask Slashdot: What's the Best Way to Retrain Old IT Workers?
    2017-12-11T11:34:00+00:00
    A medium-sized company just hired a new IT manager who wants advice from the Slashdot community about their two remaining IT "gofers": These people have literally been here their entire "careers" and are now near retirement. Quite honestly, they do not have any experience other than reinstalling Windows, binding something to the domain and the occasional driver installation -- and are more than willing to admit this. Given many people are now using Macs and most servers/workstations are running Linux, they have literally lost complete control over the company, with most of these machines sitting around completely unmanaged. Firing these people is nearly impossible. (They have a lot of goodwill within other departments, and they have quite literally worked there for more than 60 years combined.) So I've been tasked with attempting to retrain these people in the next six months. Given they still have to do work (imaging computers and fixing basic issues), what are the best ways of retraining them into basic network, Windows, Mac, Linux, and "cloud" first-level help desk support? Monster_user had some suggestions -- for example, "Don't overtrain. Select and target areas where they will be able to provide a strong impact." Any other good advice? Leave your best answers in the comments. What's the best way to retrain old IT workers?

    Read more of this story at Slashdot.

  • Google's Machine Learning Is Analyzing Data From NASA's Kepler Space Telescope
    2017-12-11T08:34:00+00:00
    NASA writes: NASA will host a media teleconference at 1 p.m. EST Thursday, Dec. 14, to announce the latest discovery made by its planet-hunting Kepler space telescope. The discovery was made by researchers using machine learning from Google. Machine learning is an approach to artificial intelligence, and demonstrates new ways of analyzing Kepler data... When Kepler launched in March 2009, scientists didn't know how common planets were beyond our solar system. Thanks to Kepler's treasure trove of discoveries, astronomers now believe there may be at least one planet orbiting every star in the sky. Space.com adds: Kepler spots alien worlds by noticing the tiny brightness dips they cause when they cross the face of their host star from the spacecraft's perspective. Kepler is the most accomplished planet hunter in history. It has found more than 2,500 confirmed alien worlds -- about 70 percent of all known exoplanets -- along with a roughly equal number of "candidates" that await confirmation by follow-up observations or analyses. The vast majority of these discoveries have come via observations that Kepler made during its original mission, which ran from 2009 to 2013. Study of these data sets is ongoing; over the past few years, researchers have used improved analysis techniques to spot many exoplanets in data that Kepler gathered a half-decade ago or more. Space.com describes Thursday's announcement as an exoplanet discovery. (Earlier they reported on the discovery of "a possibly habitable alien world" about 2.2 times the size of earth orbiting a dwarf star "within the range of distances where liquid water could exist on a world's surface".) Slashdot reader schwit1 points out that other less-credible sites speculate NASA's announcement will be "a major discovery about life beyond earth."

    Read more of this story at Slashdot.

  • Does Systemd Makes Linux Complex, Error-Prone, and Unstable?
    2017-12-11T04:32:00+00:00
    "Systemd developers split the community over a tiny detail that decreases stability significantly and increases complexity for not much real value." So argues Nico Schottelius, talking about his experiences as the CEO of a Swiss company providing VM hosting, datacenters, and high-speed fiber internet. Long-time Slashdot reader walterbyrd quotes Nico's essay: While I am writing here in flowery words, the reason to use Devuan is hard calculated costs. We are a small team at ungleich and we simply don't have the time to fix problems caused by systemd on a daily basis. This is even without calculating the security risks that come with systemd. Our objective is to create a great, easy-to-use platform for VM hosting, not to walk a tightrope... [W]hat the Devuan developers are doing is creating stability. Think about it not in a few repeating systemd bugs or about the insecurity caused by a huge, monolithic piece of software running with root privileges. Why do people favor Linux on servers over Windows? It is very easy: people don't use Windows, because it is too complex, too error prone and not suitable as a stable basis. Read it again. This is exactly what systemd introduces into Linux: error prone complexity and instability. With systemd the main advantage to using Linux is obsolete. The essay argues that while Devuan foisted another choice into the community, "it is not their fault. Creating Devuan is simply a counteraction to ensure Linux stays stable. which is of high importance for a lot of people."

    Read more of this story at Slashdot.

  • After Automating Order-Taking, Fast Food Chains Had to Hire More Workers
    2017-12-11T02:27:00+00:00
    An anonymous reader quotes the Atlantic: Blaine Hurst, the CEO and president of Panera, told me that because of its new [self-service] kiosks, and an app that allows online ordering, the chain is now processing more orders overall, which means it needs more total workers to fulfill customer demand. Starbucks patrons who use the chain's app return more frequently than those who don't, the company has said, and the greater efficiency that online ordering allows has boosted sales at busy stores during peak hours. Starbucks employed 8 percent more people in the U.S. in 2016 than it did in 2015, the year it launched the app... James Bessen, an economist at Boston University School of Law, found that as the number of ATMs in America increased fivefold from 1990 to 2010, the number of bank tellers also grew. Bessen believes that ATMs drove demand for consumer banking: No longer constrained by a branch's limited hours, consumers used banking services more frequently, and people who were unbanked opened accounts to take advantage of the new technology. Although each branch employed fewer tellers, banks added more branches, so the number of tellers grew overall. And as machines took over many basic cash-handling tasks, the nature of the tellers' job changed. They were now tasked with talking to customers about products -- a certificate of deposit, an auto loan -- which in turn made them more valuable to their employers. "It's not clear that automation in the restaurant industry will lead to job losses," Bessen told me.

    Read more of this story at Slashdot.

  • Researchers Say Human Lifespans Have Already Hit Their Peak
    2017-12-11T00:22:00+00:00
    An anonymous reader quotes Newsweek: We have reached our peak in terms of lifespan, athletic performance and height, according to a new survey of research and historical records... "These traits no longer increase, despite further continuous nutritional, medical, and scientific progress," said Jean-FranÃois Toussaint, a physiologist at Paris Descartes University, France, in a press release... For the study, published in the journal Frontiers in Physiology, a team of French scientists, including Toussaint, from a range of fields analyzed 120 years' worth of historical records and previous research to gauge the varying pace of changes seen in human athletic performance, human lifespan and human height. While, as they observe, the 20th century saw a surge in improvements in all three areas that mirrored industrial, medical and scientific advances, the pace of those advances has slowed significantly in recent years. The team looked at world records in a variety of sports, including running, swimming, skating, cycling and weight-lifting. Olympic athletes in those sports continually toppled records by impressive margins from the early 1900s to the end of the 20th century, according the study. But since then, Olympic records have shown just incremental improvements. We have stopped not only getting faster and stronger, according to the study, but also growing taller... [D]ata from the last three decades suggest that heights have plateaued among high-income countries in North America and Europe... As for our human lifespan, life expectancy in high-income countries rose by about 30 years from 1900 to 2000, according to a National Institutes of Health study cited by the authors, thanks to better nutrition, hygiene, vaccines and other medical improvements. But we may have maxed out our biological limit for longevity. The researchers found that in many human populations, says Toussaint, "it's more and more difficult to show progress in lifespan despite the advances of science."

    Read more of this story at Slashdot.

  • Launch of Bitcoin Futures Trading Crashes CBOE Site
    2017-12-10T23:17:00+00:00
    "5PM CT is the start of Bitcoin futures trading and the $CBOE website appears to be down," one market watcher posted on Twitter (and his observation was quickly confirmed by other cryptocurrency-watching accounts and confirmed by CBOE). "I'm guessing watching Bitcoin futures start trading is a more popular spectator sport than anticipated." Bitcoin futures will also begin trading on the Chicago Mercantile Exchange in eight days. The Street report that the anticipation of that "has triggered wild swings in bitcoin prices over the last week." Overall, trading bitcoin futures is a positive development for the cryptocurrency says the research team at Fundstrat... The introduction of derivatives lays the necessary market structure for institutions to allocate cash towards cryptocurrencies, points out Fundstrat... Short sellers may now express negative views on bitcoin, which could lead to short-term pricing pressure. But the ability for short sellers to hate on bitcoin could be viewed as a longer term positive, Fundstrat says. Shorting essentially creates true price discovery and means that hedge funds could take bitcoin more seriously. This should improve the long-term prospects of bitcoin as it broadens sponsorship, Fundstrat believes.

    Read more of this story at Slashdot.

  • Top iOS Apps of 2017: Bitmoji Beats Snapchat, YouTube, and Facebook Messenger
    2017-12-10T22:27:00+00:00
    An anonymous reader quotes CNN: Apple has unveiled its list of most downloaded iOS apps of the year, and topping the list is free custom emoji app Bitmoji... Bitmoji soared to the top of the list, thanks to an integration with Snapchat. (Snapchat's parent company acquired Bitmoji last year for an unknown amount)... Users must download the Bitmoji app to use it with Snapchat. Fittingly, the main Snapchat app took second place, despite a tough year on Wall Street that was attributed to slow user growth. Snapchat was the most downloaded app of 2016. Google's YouTube took the number three spot this year, while Facebook's Messenger and Instagram placed fourth and fifth, respectively.

    Read more of this story at Slashdot.

  • Coinbase Warns During Times of High Volatility, Access Could Become 'Unavailable'
    2017-12-10T21:22:00+00:00
    An anonymous reader quotes City AM: A leading bitcoin exchange has warned that customers may be unable to get their money out quickly in the event of a crash in the cryptocurrency's price. Writing in a blog post last week, Coinbase's co-founder and chief executive Brian Armstrong, said despite "sizeable and ongoing" increases in the firm's technical infrastructure and engineering staff, access to Coinbase services could become "degraded or unavailable during times of significant volatility or volume. This could result in the inability to buy or sell for period of time," he said. Armstrong added that there would be restrictions on how much customers could sell, or sell limits, to "protect client accounts and assets"... Bitcoin's market capitalisation rose above $300 billion for the first time earlier this week when its price rocketed to an all-time high of just over $17,000. Many analysts have warned that bitcoin represents an unsustainable bubble, though no one is quite sure when it will burst.

    Read more of this story at Slashdot.

  • Exhausted Amazon Drivers Are Working 11-Hour Shifts For Less Than Minimum Wage
    2017-12-10T20:17:00+00:00
    schwit1 quotes the Daily Mirror: Drivers are being asked to deliver up to 200 parcels a day for Amazon while earning less than the minimum wage, a Sunday Mirror investigation reveals today... Many routinely exceed the legal maximum shift of 11 hours and finish their days dead on their feet. Yet they have so little time for food or toilet stops they snatch hurried meals on the run and urinate into plastic bottles they keep in their vans. They say they often break speed limits to meet targets that take no account of delays such as ice, traffic jams or road closures. Many claim they are employed in a way that means they have no rights to holiday or sickness pay. And some say they take home as little as £160 for a five-day week amid conditions described by one lawyer as "almost Dickensian"... The Driving and Vehicle Standards Agency has vowed to investigate after drivers contacted them to complain about conditions.

    Read more of this story at Slashdot.

 

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

Mathematics Department
Duke University, Box 90320
Durham, NC 27708-0320