Author : Alexander Barg, Department of Electrical and Computer Engineering, University of Maryland
Pages : 115
Publication Date : Oct 1997
Document Summary:
This paper deals with complexity issues in the theory of linear error-correcting codes. Algorithmic problems that this paper study are constructing good codes, encoding and decoding them. According to their complexity, problems are divided into easy, i.e., polynomial in the length n of the code, and difficult, i.e., exponential ones. The first part deals with easy problems. This paper presents a construction of codes that correct a linear fraction of errors with complexity n log n. The construction is based on well-known since the late 80ies explicit constructions of good expanding graphs. Another group of problems in this part is related to codes for non-Hamming errors, namely, erasures, defects (codes for memories with defective cells), and localized errors.
The second part, which forms the core of this paper, deals with difficult problems, first and foremost, maximum likelihood decoding of linear codes. This paper studies separately the complexity of hard-decision and soft-decision decoding. For the hard-decision decoding case this paper presents algorithms grouped in two classes, gradient-like decoding and information-set decoding. It turns out that this general approach is sufficient to study most if not all known general decoding methods. In the soft-decision decoding context, this paper first discuss possible problem settings and then implementations of decoding with reduced complexity.
The last part of the paper overviews most known NP-hard decoding problems including some recent nonapproximability results.
The supporting material includes many general properties of linear codes from well-known to rather sophisticated, and a brief discussion of models of computations and relevant settings for the study of complexity issues in coding theory. This paper also gives examples of many methods studied. Sometimes they just illustrate concepts and definitions, but sometimes capture the most essential features of the proofs and on occasion even replace them.
Generally this paper gives complete and self-contained proofs of the results.
The coverage is extended from classical algorithms up to very recent developments. This paper thoroughly study and compare different algorithms, especially those applicable to several seemingly non-related problems. This unified approach to algorithmic coding problems enables us to organize previously independent results in a self-contained part of coding theory.
This information is taken from- http://www.freetechbooks.com/complexity-issues-in-coding-theory-t527.html
Sunday, January 16, 2011
Thursday, December 30, 2010
EXTRA-DIMENSIONAL
This February, you'll be able to enjoy an extra dimension with the release of CAPTAIN WONDER 3D from Image Comics -- a comic book featuring the most advanced 3D ever used in the medium!
This 48-page one shot is from comics superstars Brian Haberlin (WITCHBLADE, SPAWN, ARIA) and Philip Tan (Green Lantern, X-Men, SPAWN), who share writing and art duties in this thrilling superhero tale. 3D glasses are included!
"With CAPTAIN WONDER, we developed an all-new 3D process, making this hands down the best 3D in comics," exclaims Haberlin. "We're sure we put the wonder back into comics with this book, and comics fans of all ages will not be disappointed."
Tan says, "Working on Captain Wonder was so much fun, creating a world, new villains, new heroes... It was a blast to work on, and it's a blast to read. So much new stuff out there is dark these days -- it was great to help create something that was fun and light!"
Captain Wonder is the superhero of this world -- he's saved millions of people during his 24-year career. But now everything is going to Hell in a hand basket: Captain Wonder has been missing for the last two months, and the harmony he so carefully protected is beginning to crumble. What happened to Captain Wonder, and when will he return? The answer may lie with Billy Gordon, a 10-year-old boy who may be in danger himself and may be the world's only hope!
CAPTAIN WONDER 3D, a 48-page full-color one-shot featuring the most advanced 3D technology in comics and the glasses to view it, will be in stores February 16, 2011, for $4.99.
to know more information check.... http://www.imagecomics.com/
Tuesday, November 16, 2010
Information, the new material
Mike Kuniavsky is a writer, designer, researcher and entrepreneur. He's the author of Observing the User Experience and Smart Things: Ubiquitous Computing User Experience Design. He is a co-founder of ThingM, an electronic hardware design, development and manufacturing company, and was a founding partner of Adaptive Path.
The mundane things around us are quietly getting a lot smarter, fundamentally changing how everyday objects are designed. Anoto pens, Roombas and Tickle Me Elmos are all computers at heart, but little resemble their word processor-running/DOOM-playing ancestors.
Thanks to Moore's Law it is now nearly as easy (and cheap) to incorporate information processing into a mass-produced object as it is to create a custom injection-molded plastic part. The capability to manipulate information and create behavior has become a component instead of the goal of digital product design. Soon, Internet-connectivity for bathroom scales and wireless sensors in running shoes will be expected options, like color and finish. We will take for granted parking meters that send us messages before they run out, just as we take for granted Bluetooth headsets, MP3 players and Netflix streaming.
This movement towards computational objects that don't look like what we currently describe as computers represents a fundamental shift in the design of technology. It blurs the edges between industrial design, product design, architecture and interaction design. It's been called many terms ("pervasive computing," "ambient intelligence," "The Internet of Things", etc.). I use "ubiquitous computing," the name Xerox PARC gave the trend in the late 1980s.
Ubicomp has been a long time coming. Xerox PARC made good progress in the early 90s (see this 1991 video), and momentum to develop useful embedded computing devices was starting to build, but then the Web hit. Attention and investment shifted to the Web, which only required traditional computers with a screen, keyboard and mouse. Digital hardware came to mean lighter laptops and mobile phones. Ubicomp disappeared from the public eye for a decade.
However, it didn't actually vanish. At the edges, outside of the mainstream consumer electronics and personal computer worlds, using small processors to create interesting behaviors became increasingly popular. Adding a cheap processor and some clever mechanics in a $15 plush toy let retailers sell Tickle Me Elmos for $35. Toy designers did not think of themselves as being in the computer business, because they (and other groups, such as car designers) used information processing tactically as a way to differentiate in a competitive market.
Now, mainstream ubicomp is coming back. The success of Internet services on mobile phones demonstrates that networked products can stretch beyond a laptop browser. The prices for CPUs have fallen below a threshold where incorporating them becomes a competitively viable business decision. Research labs have developed new technologies for embedding information processing in virtually anything. New businesses, such as FitBit, and Green Goose are based on the fact that processing is cheap, and you can include it in anything.
The idea of a single general-purpose "computation" device is fading into the same historical background as having a single steam engine to power a whole factory, or a single electric motor to power every appliance in a house. As it fades, designers and developers have to learn to design smart things that serve the interests, abilities, and needs of people. We must create a practice of ubiquitous computing user experience design.
This article is taken from- http://www.boingboing.net/2010/11/02/information-the-new-material.html
The mundane things around us are quietly getting a lot smarter, fundamentally changing how everyday objects are designed. Anoto pens, Roombas and Tickle Me Elmos are all computers at heart, but little resemble their word processor-running/DOOM-playing ancestors.
Thanks to Moore's Law it is now nearly as easy (and cheap) to incorporate information processing into a mass-produced object as it is to create a custom injection-molded plastic part. The capability to manipulate information and create behavior has become a component instead of the goal of digital product design. Soon, Internet-connectivity for bathroom scales and wireless sensors in running shoes will be expected options, like color and finish. We will take for granted parking meters that send us messages before they run out, just as we take for granted Bluetooth headsets, MP3 players and Netflix streaming.
This movement towards computational objects that don't look like what we currently describe as computers represents a fundamental shift in the design of technology. It blurs the edges between industrial design, product design, architecture and interaction design. It's been called many terms ("pervasive computing," "ambient intelligence," "The Internet of Things", etc.). I use "ubiquitous computing," the name Xerox PARC gave the trend in the late 1980s.
Ubicomp has been a long time coming. Xerox PARC made good progress in the early 90s (see this 1991 video), and momentum to develop useful embedded computing devices was starting to build, but then the Web hit. Attention and investment shifted to the Web, which only required traditional computers with a screen, keyboard and mouse. Digital hardware came to mean lighter laptops and mobile phones. Ubicomp disappeared from the public eye for a decade.
However, it didn't actually vanish. At the edges, outside of the mainstream consumer electronics and personal computer worlds, using small processors to create interesting behaviors became increasingly popular. Adding a cheap processor and some clever mechanics in a $15 plush toy let retailers sell Tickle Me Elmos for $35. Toy designers did not think of themselves as being in the computer business, because they (and other groups, such as car designers) used information processing tactically as a way to differentiate in a competitive market.
Now, mainstream ubicomp is coming back. The success of Internet services on mobile phones demonstrates that networked products can stretch beyond a laptop browser. The prices for CPUs have fallen below a threshold where incorporating them becomes a competitively viable business decision. Research labs have developed new technologies for embedding information processing in virtually anything. New businesses, such as FitBit, and Green Goose are based on the fact that processing is cheap, and you can include it in anything.
The idea of a single general-purpose "computation" device is fading into the same historical background as having a single steam engine to power a whole factory, or a single electric motor to power every appliance in a house. As it fades, designers and developers have to learn to design smart things that serve the interests, abilities, and needs of people. We must create a practice of ubiquitous computing user experience design.
This article is taken from- http://www.boingboing.net/2010/11/02/information-the-new-material.html
Intent to Kill (2009) [Novel]
by James Grippando
Summary (From the publisher):
Original languages: English
this article is taken fr5om- http://www.iblist.com/book69219.htm
Summary (From the publisher):
"I know who did it." That was the message sent to prosecuting attorney Emma Carlisle on the third anniversary of Chelsea James's death. Everyone believed Chelsea was killed in a hit and run accident, but the anonymously sent note indicated that there was an intent to kill. Ryan James, a star minor league player, was poised for the major leagues. But after losing his beloved Chelsea, his dreams of baseball fame turned to ashes. Though he suffers from insomnia, he has become a popular "shock Jock" at a Boston radio station and he's raising his six-year-old daughter on his own. His life is somewhat coming back to normal when Emma contacts him about the strange note she was sent. While it seems highly unlikely, both suspect that Chelsea's brother, Babes, who suffers from Asperger's Syndrome, sent the note and may know something about what really happened at the scene of the crime.
A second anonymous note sends everyone into a tailspin. Suddenly Babes goes missing only to call into Ryan's radio show and announce on the air that he killed his sister. Now the police are hunting down Babes while Ryan and Emma are racing against the clock to uncover the truth and at the same time find Babes before he gets hurt.
Original title: Intent to KillA second anonymous note sends everyone into a tailspin. Suddenly Babes goes missing only to call into Ryan's radio show and announce on the air that he killed his sister. Now the police are hunting down Babes while Ryan and Emma are racing against the clock to uncover the truth and at the same time find Babes before he gets hurt.
Original languages: English
this article is taken fr5om- http://www.iblist.com/book69219.htm
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