30 Years of the Digest ... founded August 21, 1981
The Telecom Digest for March 21, 2012
====== 30 years of TELECOM Digest -- Founded August 21, 1981 ======
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Date: Mon, 19 Mar 2012 23:16:33 -0400 From: Monty Solomon <firstname.lastname@example.org> To: email@example.com. Subject: Free apps eat up your phone battery just sending ads Message-ID: <firstname.lastname@example.org> Free apps eat up your phone battery just sending ads by Jacob Aron 18 March 2012 STRUGGLING to make your smartphone battery last the whole day? Paying for your apps might help. Up to 75 per cent of the energy used by free versions of Android apps is spent serving up ads or tracking and uploading user data: running just one app could drain your battery in around 90 minutes. Abhinav Pathak, a computer scientist at Purdue University, Indiana, and colleagues made the discovery after developing software to analyse apps' energy usage. When they looked at popular apps such as Angry Birds, Free Chess and NYTimes they found that only 10 to 30 per cent of the energy was spent powering the app's core function. ... http://www.newscientist.com/article/mg21328566.400-free-apps-eat-up-your-phone-battery-just-sending-ads.html -or- http://tinyurl.com/75tgvn3 ***** Moderator's Note ***** TANSTAAFL. Bill Horne Moderator
Date: Tue, 20 Mar 2012 00:06:34 -0400 From: Monty Solomon <email@example.com> To: firstname.lastname@example.org. Subject: What Hath Bell Labs Wrought? The Future Message-ID: <email@example.com> THE IDEA FACTORY Bell Labs and the Great Age of American Innovation By Jon Gertner >422 pages. The Penguin Press. $29.95 What Hath Bell Labs Wrought? The Future By MICHIKO KAKUTANI March 19, 2012 In today's world of Apple, Google and Facebook, the name may not ring any bells for most readers, but for decades - from the 1920s through the 1980s - Bell Labs, the research and development wing of AT&T, was the most innovative scientific organization in the world. As Jon Gertner argues in his riveting new book, "The Idea Factory," it was where the future was invented. Indeed, Bell Labs was behind many of the innovations that have come to define modern life, including the transistor (the building block of all digital products), the laser, the silicon solar cell and the computer operating system called Unix (which would serve as the basis for a host of other computer languages). Bell Labs developed the first communications satellites, the first cellular telephone systems and the first fiber-optic cable systems. The Bell Labs scientist Claude Elwood Shannon effectively founded the field of information theory, which would revolutionize thinking about communications; other Bell Labs researchers helped push the boundaries of physics, chemistry and mathematics, while defining new industrial processes like quality control. In "The Idea Factory," Mr. Gertner - an editor at Fast Company magazine and a writer for The New York Times Magazine - not only gives us spirited portraits of the scientists behind Bell Labs' phenomenal success, but he also looks at the reasons that research organization became such a fount of innovation, laying the groundwork for the networked world we now live in. ... http://www.nytimes.com/2012/03/20/books/the-idea-factory-by-jon-gertner.html -or- http://tinyurl.com/6t2ct22 ***** Moderator's Note ***** I'm always wary of lionizing organizations or people that I don't know personnaly. Bell Labs made mistakes as well as breakthroughs, and it was always cursed by a gap between its blackboards and its breadboards. The feeling of the scientists and engineers at the labs was that manufacturing was Western Electric's business, and since the labs were actually a subsidiary of WE, there was a potent driver for a "We just design 'em" culture that limited many of the Labs' projects to theoretical advances. The gap between the Labs and the field caused some very severe errors: most notably, the choice of an 8,000 Hz sample rate for the T-1 carrier system. Although it was Shannon's work that predicted the need for a sample rate of at least twice the highest frequency to be reproduced, the T-1 designers didn't do the field trials which would have revealed that sampling ambiguities at even sub-multiples of the "chop" rate would make 1,000 Hz test tones unusable. This is the reason that "Milliwatt" test tones are now slightly offset from 1,000 Hz - but I can only imaging the cost of rework and redesign that far-reaching error caused. Bill Horne Moderator
Date: Tue, 20 Mar 2012 20:38:11 -0700 (PDT) From: HAncock4 <firstname.lastname@example.org> To: email@example.com. Subject: Re: What Hath Bell Labs Wrought? The Future Message-ID: <firstname.lastname@example.org> ***** Moderator's Note ***** > The gap between the Labs and the field caused some very severe errors: > most notably, the choice of an 8,000 Hz sample rate for the T-1 > carrier system. Although it was Shannon's work that predicted the need > for a sample rate of at least twice the highest frequency to be > reproduced, the T-1 designers didn't do the field trials which would > have revealed that sampling ambiguities at even sub-multiples of the > "chop" rate would make 1,000 Hz test tones unusable. This is the > reason that "Milliwatt" test tones are now slightly offset from 1,000 > Hz - but I can only imaging the cost of rework and redesign that > far-reaching error caused. Could you elaborate on this in layman's terms--particularly the statement-- "sampling ambiguities at even sub-multiples of the "chop" rate would make 1,000 Hz test tones unusable"? It would seem to me that 8,000 Hz sample rate would make sense because it was double the voice band of 4,000 Hz. Thanks. ***** Moderator's Note ***** I didn't write that clearly: it's not "even sub-multiples", it's "rational sub-multiples", i.e., sub-multiples that evenly divide into 8,000 Hz. Bill Horne Moderator
Date: Tue, 20 Mar 2012 16:38:25 -0700 (PDT) From: Joseph Singer <email@example.com> To: firstname.lastname@example.org. Subject: Public smart phones Message-ID: <1332286705.62741.YahooMailClassic@web161505.mail.bf1.yahoo.com> It's the cellphone of last resort. New Yorkers stuck with a battery-drained iPad or BlackBerry will soon be able to turn to the city's newest "pay phones" -- computer kiosks that let users buy access to the Web, e-mail and various apps. http://www.nypost.com/p/news/local/public_smart_phones_BadgbBQ9KB9wSimdMTF3rJ?utm_medium=rss&utm_content=Local -or- http://goo.gl/IjAFj
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