Machine Design Blogs

The headline from the news blog of the Chronicle of Higher Education screams that a third of public school students need remediation at college. Read the item, though, and it is clear that the there is less to the headline than meets the eye, and the news may be less alarming than it first appears.

First, they are only referring to public school students who continued on to college. So it is obvious that the proportion of public school graduates who needed remediation is less than one third. It is actually one third of those who continued on to college, not one third of the total population of public school graduates.

And the report is not clear on whether the figure only references those who went on to four-year schools, or those who also went on to community college. It would seem to include both groups. If that’s the case, therein may lie an explanation for the large amount of remediation. Most people continue on to four year schools to pursue a profession. Some continue on to community college to pursue a profession, but many more go there to get a vocation. There is a difference in preparation between the two groups.

Finally, it turns out that what they mean by “needing remediation” is that the student took at least one remedial course. It would be interesting to see how many took one and only one remedial course.

It would also be interesting to find you what passes for a remedial course these days. I know what it was like back in my day. If the college admitted you with math SATs that weren’t quite up to snuff, you might have wound up in a remedial calculus course. They covered the same material as the regular freshman calculus course and took the same exams. But they met more frequently to give more classroom time, and they were run by the same teaching fellows running the regular classes. Their “remedial” nature was minimal.

http://chronicle.com/news/article/4057/a-third-of-public-school-students-in-mass-need-remediation-at-college-report-says?utm_source=at&utm_medium=en

According to a study by the American Council for an Energy Efficient Economy (ACEEE), it takes the U.S. less than half the energy to produce a dollar of economic output now that it did in 1970.

Also ccording ACEEE, every extra kilowatt-hour demanded by Internet and communications technologies produces a ten-fold energy savings in the U.S. economy.

So now when you are surfing American Idol fan sites, you can be secure in the knowledge that you are actually saving energy!

The report states, “Since 1970… U.S. energy consumption per dollar of economic output has declined from 18,000 British Thermal Units (Btus) to about 9,000 Btus in 2008. Through that energy efficiency we have met approximately 75 percent of our new demand for energy.”

Energy intensity (Units of Energy used to produce a unit of Gross Domestic Product) declined 1.8 percent per year between 1970 and 1995. As new internet and communications technologies forged onto the scene between 1996 and 2006, energy intensity declined at a much more rapid rate of 2.4 percent.

Well, it’s not just because of outsourcing from big companies, at least according to this research paper by a couple of economists.

What Accounts for the Rising Sophistication of China’s Exports?

> by Zhi Wang, Shang-Jin Wei - #13771 (ITI)

>

> Abstract:

>

> Chinese exports have become increasingly sophisticated. This has

> generated anxiety in developed countries as competitive pressure may

> increasingly be felt outside labor-intensive industries. Using

> product-level data on exports from different cities within China, this

> paper investigates the contributing factors to China’s rising export

> sophistication. Somewhat surprisingly, neither processing trade nor

> foreign invested firms are found to play an important role in

> generating the increased overlap between Chinaâ?Ts export structure

> and that of high-income countries. Instead, improvement in human

> capital and government policies in the form of tax-favored high-tech

> zones appear to be the key to the country’s evolving export structure.

> On the other hand, processing trade, foreign invested firms, and

> government-sponsored high-tech zones all have contributed

> significantly to raising the unit values of Chinese exports within a

> given product category.

>

> http://papers.nber.org/papers/W13771

Turns out you can read out the contents of DRAM from a laptop for anywhere from a few seconds to a few minutes after the machine is off. Blasting the chips with the contents of a compressed air can slows the rate at which data decays. Of course, you need access to the machine either while it is on or shortly after it has been turned off for his scam to work. The encrypted data on disk drives is also at risk with the right techniques, as the video on this pages shows.

http://chronicle.com/wiredcampus/article/2764/with-a-can-of-air-hackers-can-steal-encrypted-data-from-laptops?utm_source=at&utm_medium=en

If you check out this demo of a prize winning video game

http://www.kloonigames.com/crayon/

I think you will agree it is a pretty cool idea. According to an item in the Chronicle of Higher Education, the creator now wishes he hadn’t posted a video of it on YouTube. It seems there are already copycat games coming out that steal his thunder:

http://chronicle.com/wiredcampus/article/2763/carnegie-mellon-student-learns-a-pitfall-of-youtube?utm_source=at&utm_medium=en

Here’s an interesting idea: The slow fall of a mass spins a rotor that powers 10 high-output LEDs. A Virginia Tech student made a lamp using this concept which you can read about here:

http://www.newswise.com/articles/view/537851/?sc=swtr

It is about four feet high and apparently operates more of less the same as an hourglass. But they don’t say how often you have to tip the thing over.

An interesting news release out this morning

http://www.newswise.com/articles/view/537915/?sc=swtr

is about a paper written by a professor at the University of California, Berkeley’s Haas School of Business and director of the UC Energy Institute. He says even after considering that solar panels reduce greenhouse gases, their costs outwigh their benefits by a wide margin. One of his conclusions:

His analysis deconstructs the argument that solar panels produce power at the location of the end-user and therefore can reduce the costs of transmission and distribution infrastructure investments. Examining 26,522 solar PV systems in California, Borenstein found they are not concentrated in locations where they would reduce transmission congestion and reduce the need for investment in transmission infrastructure.

Interestingly, he figures solar would make more sense if the cost of electricity were allowed to rise as demand increases. That would let the electricity panels generate be worth more because it would come at times of the day when demand from industrial sources were highest.

Userful says it’s giving away its Desktop Multiplier software, which turns one computer into several. The company says all you need do is connect an extra monitor, USB keyboard, and mouse to a computer box, and the software lets more than one user work on the PC at the same time.

Why are they giving the software away? “Everybody likes something for free, and it doesn’t get much better than a free PC with zero environmental footprint,” says company President Tim Griffin. “We hope that people will see how well the software works at home, and start recommending it to their workplaces and schools as a way to help save the environment while cutting IT costs. A so-called ‘live CD’ lets you transform almost any PC almost anywhere into a several-user computer.”

The software can create up to 10 independent workstations from a single standard PC box. The company says the software is already being used in schools, libraries, hotels, and businesses around the world. Download a free two-user license.

Go to Dr. Ray Ridley’s Ridley Engineering site and look at the page listing his publications and a short description of each one. The paper described at the very botom is a hoot. Here is part of the description:

This is at the bottom of the list for a good reason. An interesting paper, it seems to make a lot of sense. Unfortunately, for current-mode control, most of it is wrong, due to an early error in modulator gain! ………………… Don’t read this paper unless you are particularly curious. The best lesson contained in this paper: don’t believe everything that you read, publication is not necessarily an indication of accuracy.

Mind you, he is referring to a paper published in the IEEE Transactions on Power Electronics. Apparently none of the reviewers caught the mistake.

You can find this here: http://www.ridleyengineering.com/papers.htm