Category Archives: Technology

YouTube Access Denied

Millions of users around the globe could not access YouTube for a couple hours yesterday. Why?

Well to understand, we need to start with how you normally connect to a web site. You click on a link to youtube.com. Your ISP looks up the internet address for youtube.com by looking at internet routing tables. Each domain has a name server that provides the IP address for where it should be found (for example, an IP address that shows youtube.com is 208.65.153.238).

Well what happened in this case is Pakistan decided to prevent anyone in Pakistan from accessing YouTube because the government didn’t like some video. The way Pakistan decided to accomplish this was to update their routing table to just direct all traffic that was meant to go to YouTube to a phony address which would then return nothing.

Why did many outside of Pakistan lose access to YouTube? Well their version of the routing table leaked out of Pakistan through PCCW (large internet provider), Then other internet providers adopted the incorrect information, until many around the globe were being directed to the wrong place.

You might find it amazing the routing system could allow such a thing to happen – it doesn’t seem very secure. You are right, that it doesn’t seem very sensible. When the internet was created some protocols were established that made sense then but don’t necessarily make sense for what the internet has become.

The problem was fixed when Google’s YouTube engineers contacted PCCW to inform them of the problem and have them correct it. I think if it was my site instead, I would have had difficulty figure out what was going on 🙂 Once PCCW corrected their routing tables the fixed flowed through the system and everyone was able to see the great stuff like Marissa Mayer discussing Innovation at Google.

I would imagine Internet2 (well on its way to a computer near you) and IPv6 will take not be so venerable to such a mistake.

Car Powered Using Compressed Air

car powered using compressed air

Jules Verne predicted cars would run on air. The Air Car (link broken, so it was removed) is making that a reality. The car is powered by compressed air which certainly seems like an interesting idea. Air car ready for production (link broken, so it was removed, sigh, when will site stop failing the web so badly?):

Refueling is simple and will only take a few minutes. That is, if you live nearby a gas station with custom air compressor units. The cost of a fill up is approximately $2.00. If a driver doesn’t have access to a compressor station, they will be able to plug into the electrical grid and use the car’s built-in compressor to refill the tank in about 4 hours.

The car is said to have a driving range of 125 miles so by my calculation it would cost about 1.6 cents per mile. A car that gets 31 mpg would use 4 gallons to go 124 miles. At $3 a gallon for gas, the cost is $12 for fuel or about 9.7 cents per mile. I didn’t notice anything about maintenance costs. I don’t see any reason why the Air Car would cost more to maintain than a normal car.

The air car was named one of Time magazine’s best inventions of the 2007.

Five-seat concept car runs on air

An engineer has promised that within a year he will start selling a car that runs on compressed air, producing no emissions at all in town. The OneCAT will be a five-seater with a fibre-glass body, weighing just 350kg and could cost just over Â£2,500.
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Tata is the only big firm he’ll license to sell the car – and they are limited to India. For the rest of the world he hopes to persuade hundreds of investors to set up their own factories, making the car from 80% locally-sourced materials.
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“Imagine we will be able to save all those components traveling the world and all those transporters.” He wants each local factory to sell its own cars to cut out the middle man and he aims for 1% of global sales – about 680,000 per year. Terry Spall from the Institution of Mechanical Engineers says: “I really hope he succeeds. It is a really brave experiment in producing a sustainable car.”

One Step Closer to Holographic TV

UA team creates new holographic display

A 3-D holographic image that can be updated and viewed without special glasses may soon find its way from a UA optics lab to operating rooms and battlefield command centers.
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That holographic bird on your credit card can’t turn into something else every few minutes, but Tay’s display can take an image rendered in three dimensions — initially photographed or computer-generated — and display it on the display surface, followed by another and another.

In addition, the device requires no special glasses or headgear to see the image, unlike present-day virtual-reality systems.
The scientists who worked on the device first speak of using it as an aid in brain surgery or as a close-to-real-time battlefield display, but Tay and UA optical sciences professor Nasser Peyghambarian are not unaware of its much more commercial potential.
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The heart of the innovation, says Tay, is the photorefractive polymer — a thin plastic film that reacts to light — that can hold an image indefinitely and be updated. Tay says the method that allowed the polymer to hold the image and update it came to him “out of the blue” while at a meeting about that very problem.
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Cramming the pinball- machine-size collection of equipment into a “table-top” commercial unit is also possible, Tay says, but a challenge. Tay says the work, which started about two years ago, was done in collaboration with Nitto Denko Technical Corp. and was funded by the U.S. Air Force Office of Scientific Research.

Energy-Efficient Microchip

Team develops energy-efficient microchip

The key to the improvement in energy efficiency was to find ways of making the circuits on the chip work at a voltage level much lower than usual, Chandrakasan explains. While most current chips operate at around one volt, the new design works at just 0.3 volts.

Reducing the operating voltage, however, is not as simple as it might sound, because existing microchips have been optimized for many years to operate at the higher standard-voltage level. “Memory and logic circuits have to be redesigned to operate at very low power supply voltages,” Chandrakasan says.

One key to the new design, he says, was to build a high-efficiency DC-to-DC converter–which reduces the voltage to the lower level–right on the same chip, reducing the number of separate components. The redesigned memory and logic, along with the DC-to-DC converter, are all integrated to realize a complete system-on-a-chip solution.

One of the biggest problems the team had to overcome was the variability that occurs in typical chip manufacturing. At lower voltage levels, variations and imperfections in the silicon chip become more problematic. “Designing the chip to minimize its vulnerability to such variations is a big part of our strategy,” Chandrakasan says. “So far the new chip is a proof of concept. Commercial applications could become available “in five years, maybe even sooner, in a number of exciting areas”

Teach Yourself Programming in Ten Years

Teach Yourself Programming in Ten Years by Peter Norvig

Get interested in programming, and do some because it is fun. Make sure that it keeps being enough fun so that you will be willing to put in ten years.
Talk to other programmers; read other programs. This is more important than any book or training course.
Program. The best kind of learning is learning by doing. To put it more technically, “the maximal level of performance for individuals in a given domain is not attained automatically as a function of extended experience, but the level of performance can be increased even by highly experienced individuals as a result of deliberate efforts to improve.” (p. 366)

IT Employment Hits New High Again

Damn the Economy! IT Employment Rises to New Heights

Unemployment among business-technology professionals has fallen to a decade low as the size of the IT workforce has risen to a record level in 2007, according to CIO Insight analysis of U.S. Bureau of Labor Statistics data. Joblessness among American IT workers averaged 2.1 percent last year, down from 2.5 percent in 2006. That’s the lowest unemployment rate for IT pros since the government began using the current method to track employment in 2000, when IT joblessness stood at 2.2 percent.

In 2007, according to our analysis, 3,758,000 workers in the U.S. held IT jobs; another 79,000 people who consider themselves business-technology professionals were unemployed. IT employment grew 8.5 percent last year. By this calculation, IT managers and staffers represent nearly 2.6 percent of employed U.S. workers in 2007.

Who Killed the Software Engineer?

Computer Science Education: Where Are the Software Engineers of Tomorrow? by Dr. Robert B.K. Dewar and Dr. Edmond Schonberg

Over the last few years we have noticed worrisome trends in CS education. The following represents a summary of those trends:
1. Mathematics requirements in CS programs are shrinking.
2. The development of programming skills in several languages is giving way to cookbook approaches using large libraries and special-purpose packages.
3. The resulting set of skills is insufficient for today’s software industry (in particular for safety and security purposes) and, unfortunately, matches well what the outsourcing industry can offer. We are training easily replaceable professionals.
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As faculty members at New York University for decades, we have regretted the introduction of Java as a first language of instruction for most computer science majors. We have seen how this choice has weakened the formation of our students, as reflected in their performance in systems and architecture courses.
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Every programmer must be comfortable with functional programming and with the important notion of referential transparency. Even though most programmers find imperative programming more intuitive, they must recognize that in many contexts that a functional, stateless style is clear, natural, easy to understand, and efficient to boot.

An additional benefit of the practice of Lisp is that the program is written in what amounts to abstract syntax, namely the internal representation that most compilers use between parsing and code generation. Knowing Lisp is thus an excellent preparation for any software work that involves language processing.

This is an excellent article: any CS students or those considering careers as programmers definitely should read this. Also read: Computer Science Education.

via: Who Killed the Software Engineer?

Dewar, a professor emeritus of computer science at New York University, believes that U.S. colleges are turning out programmers who are – there’s no nice way to say this – essentially incompetent.

Young IT Workers Demands

Young IT workers disillusioned, hard to hold, survey says

more than 50% of respondents described those teen and 20-something employees as the “toughest generation to manage.”
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“Millennials are coming in with high expectations and are disillusioned about the reality of a work place. They feel they should be rewarded and start at the top, when we all know you have to work your way up.
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“There is a shrinking talent pool of qualified IT professionals and some managers are talking about the graying of their current staff.

The IT job market continues to be very strong. The number of IT jobs continues to grow and remains at an all time high.

Could It Be? Data Shows U.S. Info Tech Jobs Grew 8% In 2007

Estimated employment in IT passed 3.76 million in 2007, based on the average of the BLS’ household surveys throughout the year. In 2006, employment was 3.46 million, for a gain of 292,000 jobs

Computer Science PhD Overview

A nice overview by Mor Harchol-Balter at Carnegie Mellon University on Applying to Ph.D. Programs in Computer Science:

A Ph.D. is a long, in depth research exploration of one topic. By long we’re typically talking about 6 years. By in depth we mean that at the end of the Ph.D. you will be the world expert or close to it in your particular area.
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In contrast, a Ph.D. program typically requires typically less than 10 courses during the entire 6
years (at CMU there are 5 required “core” courses, and 3 required “electives”). The emphasis in the
Ph.D. is not on classes, but rather on research.
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If you choose to be a professor at a research university, your life will consist of the following
tasks: (i) doing research on anything you like, (ii) working with graduate students, (iii) teaching
classes, (iv) applying for grants, (v) flying around to work with other researchers and to give talks
on your research, (vi) doing service for your department and school (like giving this talk). Note that
I say “your life” rather than your job, because for new faculty, your life becomes your job. It’s a
fantastic job/life for me because I love these activities, so I’m happy to work hard at all of them, but
it’s not right for everyone.

The document also offers a list of fellowships including: the NSF Graduate Research Fellowship and NDSEG Graduate Fellowship (disclosure: I work for ASEE administering part of the process for these, and other, fellowships – this blog is my own and not associated with ASEE).

Really Widescreen Monitor (2880×900)

I foolishly bought a 22 inch “widescreen” monitor (I guess I can’t call it that now) last week. What was I thinking? Seriously the video shows a 2880×900 curved monitor from Alienware is scheduled to be released in the second half of this year. No price estimate is available yet. It is actually a rear projection DLP system. Last year, in Two Screens Are Better Than One we showed a Microsoft prototype very similar to this.