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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 :-)

  • Intel Says They Aren't Abandoning 10nm Chips, Despite Report Saying They're Canceled
    2018-10-23T03:30:00+00:00
    An anonymous reader quotes a report from PC Magazine: Intel is denying a new report that claims the chipmaker is abandoning its 10 nanometer manufacturing process following years of delays. "Media reports published today that Intel is ending work on the 10nm process are untrue," the company tweeted on Monday. Hours prior to the tweet, semiconductor news site SemiAccurate claimed that Intel was pulling the plug on the chip-making technology over the company's ongoing struggles to bring it to full production. Chips built with the 10nm process were originally slated to arrive in 2016, but the company has repeatedly pushed that launch date back. During Intel's last earnings call, executives said they now expect 10nm chips to officially drop during the 2019 holiday season. In response to SemiAccurate's report, Intel said it continues to make "good progress" on the 10nm technology. "Yields are improving consistent with the timeline we shared during our last earnings report," the chipmaker added in its tweet. The next-generation silicon will supposedly offer a 25 percent performance increase over 14nm-manufactured technology. The 10nm chips will also be able to run on 50 percent less power when clocked at the same performance of a 14nm processor. Intel will hold an earnings call on Thursday, so expect company executives to elaborate on 10nm's progress then.

    Read more of this story at Slashdot.

  • YouTube Is Investing $20 Million In Educational Content, Creators
    2018-10-23T02:20:00+00:00
    YouTube is creating a new Learning Fund program where it will invest $20 million toward education content. The announcement was made today by Malik Ducard, global head of learning. The Verge reports: Channels like TED-Ed, dedicated to educational Ted Talks, and Hank and John Green's Crash Course have already secured additional funding, according to YouTube's blog post. The company plans to invest in content from independent creators, like the Green brothers, as well as traditional news sources and educational organizations to broaden its content offering. YouTube's Learning Fund has a nice ring to it, but it isn't a philanthropic charity. An FAQ about the program states that "successful applicants must enter into a written agreement with YouTube. This agreement will contain more details about required deliverables, payment timelines, and other terms and conditions." Creators must maintain a minimum of 25,000 subscribers. Those applying to the program also don't need to have a degree or proper certification in their field, "but successful applicants will be required to demonstrate that they have expertise and/or that the content they produce is verified by an expert in the field."

    Read more of this story at Slashdot.

  • Feds Shut Down Self-Driving School Bus Pilot In Florida
    2018-10-23T01:40:00+00:00
    The National Highway Traffic Safety Administration on Friday ordered the French transportation company Transdev to stop transporting schoolchildren in a self-driving vehicle in Florida. Ars Technica reports: Transdev's pilot project in Babcock Ranch, a planned community, was quite modest. On Fridays, Transdev's electric shuttle would take a group of elementary-aged children to school, then take them home later in the day. The vehicle had a safety driver on board. The route was short enough that kids walked or rode their bikes to school the other four days of the week, according to a spokeswoman for Babcock Ranch. "The shuttle travels at a top speed of 8mph, with the potential to reach speeds of 30mph once the necessary infrastructure is complete," an August press release stated. So why did the feds shut down this project while allowing lots of others to continue with minimal oversight? NHTSA points to two factors. One is that Transdev is a French company. Different countries have different safety standards, so vehicles designed overseas often can't be used in the U.S. without special permission from U.S. regulators. NHTSA granted Transdev a temporary importation authorization to test its driverless shuttle in the United States. "Transdev requested permission to use the shuttle for a specific demonstration project, not as a school bus," NHTSA said in its Friday statement. "Transdev failed to disclose or receive approval for this use." The other issue, of course, is that the project involves kids. For obvious reasons, federal regulators are going to be extra wary of testing experimental technology on schoolchildren.

    Read more of this story at Slashdot.

  • UK ISP Tests SIM Card That Forces All of Your Mobile Data Through Tor
    2018-10-23T01:00:00+00:00
    An anonymous reader quotes a report from Motherboard: [O]ne UK grassroots internet service provider is currently testing a data only SIM card that blocks any non-Tor traffic from leaving the phone at all, potentially providing a more robust way to use Tor while on the go. "This is about sticking a middle finger up to mobile filtering, mass surveillance," Gareth Llewelyn, founder of Brass Horn Communications, told Motherboard in an online chat. Brass Horn is a non-profit internet service provider with a focus on privacy and anti-surveillance services. Tor is a piece of software and a related network run by volunteers. When someone runs Tor on their computer or phone, it routes their traffic through multiple servers before reaching its final destination, such as a website. That way, the website owner can't tell who is visiting; only that someone is connecting from Tor. The most common way people access Tor is with the Tor Browser Bundle on desktop, or with the Orbot app on Android. But, in some cases, neither of these totally guarantee that all of your device's traffic will be routed through Tor. If you're using the Tor Browser Bundle on a laptop, and then go to use another piece of software, that app is probably not going to use Tor. The same might stand for Orbot running on older iterations of Android. Nathan Freitas, from The Guardian Project which maintains Orbot, said with newer versions of Android, you can lock down device traffic to only work if a specific VPN is activated, including Orbot's. This SIM card, however, is supposed to provide a more restricted solution in the event that other approaches don't quite work. The UK-exclusive SIM card requires that users create a new access point name on their device. It also requires Orbot to be installed and running on the device itself.

    Read more of this story at Slashdot.

  • Richard Branson Steps Down As Chairman of Virgin Hyperloop One
    2018-10-23T00:20:00+00:00
    Richard Branson is stepping down as chairman of Virgin Hyperloop One -- "the company that plans to build a supersonic transport system in the United Arab Emirates and other countries," reports Reuters. The reason is because the company needs a more actively involved leader. From the report: The Financial Times reported last week that Saudi Arabia had terminated a planned deal with Virgin Hyperloop One after Branson halted investment talks with Riyadh over the Jamal Khashoggi affair. "At this stage in the company's evolution, I feel it needs a more hands-on Chair, who can focus on the business and these opportunities," the statement quoted Branson as saying. "It will be difficult for me to fulfill that commitment as I already devote significant time to my philanthropic ventures and the many business within the Virgin Group."

    Read more of this story at Slashdot.

  • Netflix To Raise $2 Billion In Debt To Fund More Original Content
    2018-10-22T23:40:00+00:00
    According to a press release posted today, Netflix is planning to raise $2 billion to help fund new content, including "content acquisitions, production and development, capital expenditures, investments, working capital and potential acquisitions and strategic transactions." TechCrunch reports: The funds will be raised in the form of senior unsecured notes, denominated in U.S. dollars and euros, it said. This debt offering is the sixth time in under four years that Netflix is raising $1 billion or more through bonds, noted Variety, which was among the first to report the news. As of September 30, Netflix's long-term debt had reached $8.34 billion, up 71% from $4.89 billion in the year ago quarter, it said during its last earnings, Variety's report also noted. Netflix recently explained during its Q3 2018 earnings that it needs to continue to invest in original programming in order to remain competitive. "Content companies such as WarnerMedia and Disney/Fox are moving to self-distribute their own content; tech firms like Apple, Amazon and others are investing in premium content to enhance their distribution platforms," the letter also stated. "Amid these massive competitors on both sides, plus traditional media firms, our job is to make Netflix stand out so that when consumers have free time, they choose to spend it with our service," it had said.

    Read more of this story at Slashdot.

  • Oculus Co-founder is Leaving Facebook After Cancellation of 'Rift 2' Headset
    2018-10-22T23:00:00+00:00
    Brendan Iribe, the co-founder and former CEO of Oculus, announced today that he is leaving Facebook. From a report: Iribe is leaving Facebook following some internal shake-ups in the company's virtual reality arm last week that saw the cancellation of the company's next generation "Rift 2" PC-powered virtual reality headset, which he had been leading development of, a source close to the matter told TechCrunch. Iribe and the Facebook executive team had "fundamentally different views on the future of Oculus that grew deeper over time," and Iribe wasn't interested in a "race to the bottom" in terms of performance, we are told.

    Read more of this story at Slashdot.

  • 16-Year-Old Dethrones Tetris World Champion With Difficult Hyper-Tap Technique
    2018-10-22T22:20:00+00:00
    Over the weekend, seven-time winner Jonas Neubauer showed up at the Classic Tetris World Championship in Portland, Oregon like he has every year since it moved there in 2011. Instead of adding another championship to his name, he finished in second place this time, bested by 16-year-old Joseph Saelee who went on an amazing three-game tear. From a report: "The kid played with pure heart, the most clutch Tetris that we've seen from anyone," Neubauer said after the dust had settled. "He just really had the ability, had the natural ability, and let it shine as bright as he could in his first tournament. [It's] truly an honor to pass the torch to the new generation of Tetris players." The veteran stood on stage holding a silver trophy, his first since losing to Harry Hong in 2014, and the unlikely Saelee, tears still in his eyes, hoisted the gold to applause from the crowd at Sunday's Retro Game Expo crowd. Though Tetris came out on the NES in 1989, the Classic World Championship tournament as it exists today didn't get started until 2010 after the game's competitive scene spent most of the aughts trading strategies, high scores, and footage evidence throughout a scattered network of forums and websites. Now, top players from around the world compete annually at the Expo using the original game and controllers played on old CRTs to see who can get the highest score in individual head-to-head matchups.

    Read more of this story at Slashdot.

  • AWS CEO Andy Jassy Follows Apple In Calling For Retraction of Chinese Spy Chip Story
    2018-10-22T21:40:00+00:00
    An anonymous reader quotes a report from CNBC: Andy Jassy, the CEO of Amazon Web Services, followed Apple's lead in calling the for the retraction of Bloomberg's story about spy chips being embedded in servers. "They offered no proof, story kept changing, and showed no interest in our answers unless we could validate their theories," Jassy wrote in a tweet on Monday. "Reporters got played or took liberties. Bloomberg should retract." Apple CEO Tim Cook told Buzzfeed on Friday that the scenario Bloomberg reported never happened and that the October story in Bloomberg Businessweek should be retracted. Bloomberg alleged data center hardware used by Apple and AWS, and provided by server company Super Micro, was under surveillance by the Chinese government, even though almost all the companies named in the report denied Bloomberg's claim. Bloomberg published a denial from AWS alongside its own report, and AWS refuted the report in a more strongly worded six-paragraph blog post entitled "Setting the Record Straight on Bloomberg Businessweek's Erroneous Article." Further reading is available via The Washington Post. "Sources tell the Erik Wemple Blog that the New York Times, the Wall Street Journal and The Post have each sunk resources into confirming the story, only to come up empty-handed," the Washington Post reports. "(The Post did run a story summarizing Bloomberg's findings, along with various denials and official skepticism.) It behooves such outlets to dispatch entire teams to search for corroboration: If, indeed, it's true that China has embarked on this sort of attack, there will be a long tail of implications. No self-respecting news organization will want to be left out of those stories. 'Unlike software, hardware leaves behind a good trail of evidence. If somebody decides to go down that path, it means that they don't care about the consequences,' Stathakopoulos says.'"

    Read more of this story at Slashdot.

  • SQLite Adopts 'Monastic' Code of Conduct
    2018-10-22T21:00:00+00:00
    An anonymous reader writes: Undoubtedly in response to this politically motivated sort of claptrap, SQLite has released their own Code of Conduct. From the preamble: Having been encouraged by clients to adopt a written code of conduct, the SQLite developers elected to govern their interactions with each other, with their clients, and with the larger SQLite user community in accordance with the "instruments of good works" from chapter 4 of The Rule of St. Benedict. This code of conduct has proven its mettle in thousands of diverse communities for over 1,500 years, and has served as a baseline for many civil law codes since the time of Charlemagne. Not everyone has found SQLite's attempt informative or funny (though many did). A developer wrote, for instance, "So is the SQLite CoC thing a joke or not? If it's not a joke, f*ck this. If it is a joke, that's even worse. Your CoC should be taken seriously." A security researcher, chimed in, "This sort of stunt will make actual code of conduct discussions harder. It's not funny, helpful, or wise."

    Read more of this story at Slashdot.

  • Oxygen-Rich Liquid Water May Exist on Mars
    2018-10-22T20:20:00+00:00
    Brines suffused with the life-giving gas could offer hope for past and even present microbes on the Red Planet, according to a new study. From a report: New research suggests our neighboring world could hide enough oxygen in briny liquid water near its surface to support microbial life, opening up a wealth of potentially habitable regions across the entire planet. Although the findings do not directly measure the oxygen content of brines known to exist on the Red Planet, they constitute an important step toward determining where life could exist there today. Aerobic respiration, which relies on oxygen, is a key component of present-day life on Earth. In this process, cells take in oxygen and break it down to produce energy to drive metabolism. Mars's very low levels of atmospheric oxygen have led many scientists to dismiss the possibility of aerobic respiration there today, but the new research brings this possibility back into play. The study appears in the October 22 edition of Nature Geoscience. "Our work is calling for a complete revision for how we think about the potential for life on Mars, and the work oxygen can do, implying that if life ever existed on Mars it might have been breathing oxygen," says lead study author Vlada Stamenkovic, a researcher at NASA's Jet Propulsion Laboratory in California. "We have the potential now to understand the current habitability." Although Mars is today a freeze-dried desert, it possesses abundant reserves of subsurface water ice, as well as some amount of liquid water in the form of brines. The brines' high salt content lowers the temperature at which they freeze, allowing them to remain liquid even on Mars's frigid surface. In their new study, Stamenkovic and his colleagues coupled a model of how oxygen dissolves in brines with a model of the Martian climate. Their results revealed that pools of salty liquid at or just beneath the surface could capture the meager amounts of oxygen from the Red Planet's atmosphere, creating a reservoir that microbes might metabolically utilize. According to the research, Martian brines today could hold higher concentrations of oxygen than were present even on the early Earth -- which prior to about 2.4 billion years ago harbored only trace amounts of the gas in its air.

    Read more of this story at Slashdot.

  • Now Apps Can Track You Even After You Uninstall Them
    2018-10-22T19:37:00+00:00
    If it seems as though the app you deleted last week is suddenly popping up everywhere, it may not be mere coincidence. From a report: Companies that cater to app makers have found ways to game both iOS and Android, enabling them to figure out which users have uninstalled a given piece of software lately -- and making it easy to pelt the departed with ads aimed at winning them back. Adjust, AppsFlyer, MoEngage, Localytics, and CleverTap are among the companies that offer uninstall trackers, usually as part of a broader set of developer tools. Their customers include T-Mobile US, Spotify Technology, and Yelp. Critics say they're a fresh reason to reassess online privacy rights and limit what companies can do with user data. "Most tech companies are not giving people nuanced privacy choices, if they give them choices at all," says Jeremy Gillula, tech policy director at the Electronic Frontier Foundation, a privacy advocate. Some providers say these tracking tools are meant to measure user reaction to app updates and other changes. Jude McColgan, chief executive officer of Boston's Localytics, says he hasn't seen clients use the technology to target former users with ads. Ehren Maedge, vice president for marketing and sales at MoEngage Inc. in San Francisco, says it's up to the app makers not to do so. "The dialogue is between our customers and their end users," he says. "If they violate users' trust, it's not going to go well for them." Adjust, AppsFlyer, and CleverTap didn't respond to requests for comment, nor did T-Mobile, Spotify, or Yelp. Uninstall tracking exploits a core element of Apple's and Google's mobile operating systems: push notifications. Developers have always been able to use so-called silent push notifications to ping installed apps at regular intervals without alerting the user -- to refresh an inbox or social media feed while the app is running in the background, for example. But if the app doesn't ping the developer back, the app is logged as uninstalled, and the uninstall tracking tools add those changes to the file associated with the given mobile device's unique advertising ID, details that make it easy to identify just who's holding the phone and advertise the app to them wherever they go.

    Read more of this story at Slashdot.

  • Chinese Company Oppo is the Latest To Be Caught Cheating on Phone Benchmarks
    2018-10-22T18:12:00+00:00
    An anonymous reader shares a report: You can add another big name to the list of phone makers found cheating on benchmarks. UL Benchmarks has delisted Oppo's Find X and F7 phones from its 3DMark charts after testing from itself and news outlet Tech2 revealed that both devices were artificially ramping up processor performance when they detected the test by name. Oppo acknowledged that it always stepped things up when it detected "games or 3D Benchmarks that required high performance," but claimed that any app would run full bore if you tapped on the screen every few seconds to signal your actions. UL, however, rejected the justifications. It was clear that Oppo was looking for the benchmark by name and not the extra processing load involved, according to the outfit. Moreover, tapping wouldn't be an effective solution if Oppo treated apps equally -- you couldn't get consistent results. Further reading: Huawei Caught Cheating Performance Test For New Phones.

    Read more of this story at Slashdot.

  • A Device That Can Pull Drinking Water From the Air Just Won the Latest XPrize
    2018-10-22T17:20:00+00:00
    Two years ago, XPrize, which creates challenges that pit the brightest minds against one another, announced that it would give any startup or company $1 million that can turn thin air into water. This month, it announced that the challenge has been concluded. From a report: A new device that sits inside a shipping container can use clean energy to almost instantly bring clean drinking water anywhere -- the rooftop of an apartment building in Nairobi, a disaster zone after a hurricane in Manila, a rural village in Zimbabwe -- by pulling water from the air. The design, from the Skysource/Skywater Alliance, just won $1.5 million in the Water Abundance XPrize. The competition, which launched in 2016, asked designers to build a device that could extract at least 2,000 liters of water a day from the atmosphere (enough for the daily needs of around 100 people), use clean energy, and cost no more than 2 cents a liter. "We do a lot of first principles thinking at XPrize when we start designing these challenges," says Zenia Tata, who helped launch the prize and serves as chief impact officer of XPrize. Nearly 800 million people face water scarcity; other solutions, like desalination, are expensive. Freshwater is limited and exists in a closed system. But the atmosphere, the team realized, could be tapped as a resource. "At any given time, it holds 12 quadrillion gallons -- the number 12 with 19 zeros after it -- a very, very, big number," she says. The household needs for all 7 billion people on earth add up to only around 350 or 400 billion gallons. A handful of air-to-water devices already existed, but were fairly expensive to use. The new system, called WEDEW ("wood-to-energy deployed water") was created by combining two existing systems. One is a device called Skywater, a large box that mimics the way clouds are formed: It takes in warm air, which hits cold air and forms droplets of condensation that can be used as pure drinking water. The water is stored in a tank inside the shipping container, which can then be connected to a bottle refill station or a tap.

    Read more of this story at Slashdot.

  • Microsoft's Problem Isn't How Often it Updates Windows -- It's How It Develops It
    2018-10-22T16:40:00+00:00
    Ever since Microsoft settled on a cadence of two feature updates a year -- one in April, one in October -- the quality of its operating system (taking into consideration the volume of bugs that emerge every few days) has deteriorated, writes Peter Bright of ArsTechnica. From the story: The problem with Windows as a Service is quality. Previous issues with the feature and security updates have already shaken confidence in Microsoft's updating policy for Windows 10. While data is notably lacking, there is at the very least a popular perception that the quality of the monthly security updates has taken a dive with Windows 10 and that installation of the twice-annual feature updates as soon as they're available is madness. These complaints are long-standing, too. The unreliable updates have been a cause for concern since shortly after Windows 10's release. The latest problem has brought this to a head, with commentators saying that two feature updates a year is too many and Redmond should cut back to one, and that Microsoft needs to stop developing new features and just fix bugs. Some worry that the company is dangerously close to a serious loss of trust over updates, and for some Windows users, that trust may already have been broken. These are not the first calls for Microsoft to slow down with its feature updates -- there have been concerns that there's too much churn for both IT and consumer audiences alike to handle -- but with the obvious problems of the latest update, the calls take on a new urgency.

    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