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Power

Submission + - Arctic to be ice-free within FIVE years, not 40

Submitted by OriginalArlen
OriginalArlen writes: The BBC is reporting new research into Arctic warming to be presented at the fall American Geophysical Union meeting which describes current models of arctic sea-ice response to warming as far too conservative. The work predicts that albedo feedback, together with a greater heat input from warmer ocean currents, will lead to ice-free summers as early as 2013. This would go a long way to explaining the dramatic and accelerating loss of sea-ice in the summer of 2007, which is merely the latest in a progressively widening gap between modeled and actual sea-ice loss (as well as presenting a nicely testable short-range prediction.)

Whilst sea-ice obviously doesn't raise the sea level when it melts, a similar runaway feedback that lead to significant reductions in the Greenland or Antarctica ice sheets would cause a 6-7m sea-level rise, indisputably catastrophic for human society as well as the polar bears.
Mozilla

Submission + - More Antarctic dinosaurs 2

Submitted by RockDoctor
RockDoctor writes: The highly respected palaeontology journal Acta Palaeontologica Polonica has published its December number for free access on the web, with the headline paper concerning new discoveries of dinosaurs from Antarctica.

The first major part of these discoveries were made as isolated bones of a sauropod (a relative of the well-known Brontosaurus) which were associated with a theropod (ancestor or cousin of Tyrannosaurus rex). These specimens were discovered at an altitude of 4100m, above the Beardmore Glacier in the TransAntarctic Mountains in 1991. Further field work during the following 13 years produced more material, seemingly from the same specimens and allowed more accurate description of the sauropod and it's naming as Glacialisaurus hammeri (the reason for the genus name is obvious ; Professor Hammer lead the field expeditions under "extremely difficult conditions"). The herbivore was some 25ft long and weighed-in at 4~6 tonnes ; at the time of life, the area was between 55 and 65 degrees south, suggesting a climate similar to the Falkland Islands or Tierra del Fuego.

The popular conception of dinosaurs as slow-moving, cold-blooded animals has long been challenged by such finds of high-latitude dinosaurs. One would expect the mainstream news sites (Slashdot included) to pick up on this publication as further evidence that the dinosaurs were much more diverse than that. After all, the only significant land animals in present-day Antarctica are penguins ; penguins are birds ; birds are dinosaurs (for any meaningful use of "birds", "are" and "dinosaurs") ; so one could make a good case that Antarctica IS the continent which has been dominated by dinosaurs for the last 200 million years. Quoth the penguin : "we don't need no steenkin' furry Mammalia on this here continent!"
However, since Antarctica is probably the most Linux-laden continent on the planet, and Antarctica is also the "dinosaur continent" (as I've just argued), then some FUD-merchant is going to make the false deduction that this means Linux is a dinosaur, instead of the correct deduction that dinosaurs are really well adapted to their extreme environments.

For the editors : Why is this under Topic:Mozilla? Because it's the closest match available in the list of topics — theropod and all that jazz.
Space

Submission + - Voyager 2 finds solar system's shape is 'dented' (reuters.com)

Submitted by
Selikoff
Selikoff writes: "NASA's Voyager 2 spacecraft has found that our solar system is not round but is "dented" by the local interstellar magnetic field of deep space, space experts said on Monday. The data was gathered by the craft on its 30-year journey into the edge of the solar system when it crossed into a sweeping region called the termination shock, they said. It showed that the southern hemisphere of the solar system's heliosphere is being pushed in or "dented." Voyager 2 is the second spacecraft to enter this region of the solar system behind Voyager 1, which entered the northern region of the heliosheath in December 2004."
Programming

Submission + - what is the perfect coder's chair?

Submitted by
DragonTHC
DragonTHC writes: "I am faced with sitting for long periods of time to do the majority of my work as a consultant. It seems that truly ergonomic chairs cost more than $700 these days. What kind of office chair should I get that will save my back and keep me from getting the DVTs in my legs? What chairs are out there that I can afford on my small budget up to $300? What do other coders spend their lives sitting in?"
Mars

Submission + - Mars Rover Investigates Steamy Martian Past (nasa.gov)

Submitted by
Riding with Robots
Riding with Robots writes: "The robotic geologist Spirit, now scurrying to reach a safe haven before the harsh Martian winter sets in, has found signs that explorers say point to hot springs or fumaroles in the Red Planet's distant past. That possibility is not only interesting geologically, but potentially biologically, since those kinds of environments on Earth teem with microbial life. Meanwhile, on the other side of the planet, Opportunity continues its descent into a deep crater, where it has found other clues about the ancient waters of Mars."
Books

Submission + - The Home Library Problem Solved (blogspot.com) 1

Submitted by
Zack Grossbart
Zack Grossbart writes: "About 18 months ago I posted the following question to Ask SlashDot, "How do you organize a home library with 3,500 books?" I have read all the responses, reviewed most of the available software, and come up with a good solution described in the article The Library Problem. This article discusses various cataloging schemes, reviews cheap barcode scanners, and outlines a complete solution for organizing your home library. Now you can see an Ask SlashDot question with a definitive answer."
Quickies

Submission + - NonSilicon, 6% efficient Printable solar cell

Submitted by Anonymous Coward
An anonymous reader writes: According to nikkei.net, A dye-sensitised polymer printed solar cell from a collaboration between Toin University of Yokohama and wrapping firm Fujimori Kogyo will sample in February of next year, has three layers, and is 0.4 millimetres thin. Although energy efficiency is modest, at only six per cent, a fab will churn out 10 megawatts of dye sensitised cells a month, using more or less conventional printing techniques.
Programming

Submission + - Microsoft's Volta beefs up Javascript

Submitted by
Julie188
Julie188 writes: "Last week, Microsoft Live Labs introduced a "technology preview" version of Volta, reports blogger Mitchell Ashley. Volta is an interesting concept. It is a software development tool that attempts to convert a monolithic .NET application into a distributed app where components run on both the client (through a browser) and the server. Distributing an application isn't easy, especially if it was originally designed as a single, server-side app. What makes Volta interesting is that it can take the code targeted for the client and turn it into JavaScript. JavaScript is convenient and Web developers love it (most of the time). But software engineers hate it. It is messy. It can get very out of hand. Plus JavaScript lacks some capabilities of more robust programming languages. This is another area Volta tries to address. Bringing more programming capabilities to JavaScript could make Volta a hit. It might also allow software engineers take control of client functionality away from Web developers."
Government

Submission + - Icelandian calls White House, labelled a terrorist (go.com) 3

Submitted by Anonymous Coward
An anonymous reader writes: A 16-year-old boy in Iceland called a secret government phone number, which he thought was Bush's private number, and posed as the president of Iceland. After passing some impromptu security questions, such as President Ólafur Ragnar Grímsson's birth date (which he answered with Wikipedia), Bush's secretary told him to expect a call back. Instead, police surrounded his house and interrogated him on where he got the number, threatening to put him on a no-fly list if he didn't tell. He claims he can't remember where he got the number, but says "I must have gotten it from a friend when I was about 11 or 12."
Security

Submission + - End users behaving badly (networkworld.com)

Submitted by
bednarz
bednarz writes: "IT managers share tales of dangerous user behavior, including sharing passwords, copying sensitive information to portable storage devices, and accessing personal e-mail accounts at work. Bruce Bonsall, CISO at MassMutual Financial Group, worries most about the intertwined work and home life of most corporate employees that leaves networks open to security holes. He also gets concerned when a user population isn't as educated about security policies or potential threats as they should be. "The bad guys are going after high network staff and senior executives, which is very disturbing. The more information they use that relates to the target, the more likely someone will get tricked, even savvy end users," Bonsall says."
Programming

Submission + - Refactoring: Improving the Design of Existing Code

Submitted by
kabz
kabz writes: "Refactoring: Improving the Design of Existing Code
Martin Fowler with Kent Beck, John Brant, William Opdyke and Don Roberts.
In the Addison-Wesley Object Technology Series.

Refactoring (as I'll refer to the book from here on in) is a heavy and beautifully produced 418 page hardback book. Martin Fowler is a UK-based independent consultant who has worked on many large systems and is the author of several other books including UML-Distilled.

Refactoring is a self-help book in the tradition of Code Complete by Steve McConnell. It defines its audience clearly as working programmers and provides a set of problems, a practical and easily followed set of remedies and a rationale for applying those techniques.

Code refactoring is the process of restructuringing code in a controlled way to improve the structure and clarity of code, whilst maintaining the meaning of the code being restructured. Many maintenance problems stem from poorly written code that has become overly complex, where objects are overly familiar with each other, and where solutions implemented expeditiously contribute to the software being hard to understand and hard to add features to.

Typically refactorings are applied over a testable or local scope, with existing behavior being preserved. Refactoring as defined in this book is not about fixing bad designs, but instead should be applied at lower levels.

Testing a la Extreme Programming is emphasized as a control for ensuring that program meaning is not changed by refactoring. It is not over emphasized, and this is not a book about testing, but it is often mentioned and stays in the background through the book.

The refactorings presented in the book are not intended as a comprehensive solution for all problems, but they do offer a means to regain control of software that has been implemented poorly, or where maintenance has been shown to simply replace old bugs with newer ones.

The book is divided into two main sections, introductory material that introduces and discusses refactorings, and a lengthy taxonomy of refactorings that includes both examples and further discussion. The introductory material consists of a long worked example through simple Java code that implements printing a statement for a video store. Despite the simplicity of the code, Fowler shows in clear detail where improvements can be made, and how those improvements make the code both impressively easy to understand, and easy to maintain and add features.

Several key refactorings are demonstrated in the opening chapter including Extract Method, Move Method and Replace Conditional with Polymorphism. This is a book about programming in the object oriented paradigm, so as you might expect, the first two refactorings refer to extracting and moving object methods either into new methods, or between objects. The third example provides a means to replace special cased behavior in a single object type by deriving a sub type of the object and moving type specific code to the sub types. This is a fundamental technique in object oriented programming, and is discussed here in practical terms.

Now that several actual refactorings have been introduced, Fowler provides a solid and well thought-out discussion of the why's, when's and when not's of refactoring. For example, code can decay as features are added, and programmers special-case, or bodge additional functionality into existing objects. Fowler argues that the bitrot and decay makes software more unreliable, leads to bugs and can accelarate as the problem gets worse. Faced with these problems, refactoring should be used to improve local design and clean up and improve code, leading to better software, that is easier to maintain, easier to debug, and easier to improve with new features as requirements change.

However, there is a caveat, in that since software functionality should remain unchanged during refactoring, the process of refactoring consumes resources, but provides no easily measureable value. Fowler confronts this issue in a section that discusses how to communicate with managers, that you are performing refactoring work. He denies being subversive, but his conclusion is that refactoring should essentially be folded in with normal work as it improves the overall result.

This is a bit like goofing off on the basis that you'll think better after 20 minutes of fooseball. I'd definitely subscribe to that theory, but many others may not.

Kent Beck guests in Chapter Three for a review of the issues in typical software that suggest a refactoring may be needed. This chapter is entitled Bad Smells in Code, and most of the smells presented will be familiar to any reasonably experienced programmer, and they will be a great learning experience for less experienced programmers. I got the same feeling reading this chapter as I did when I first read Code Complete. Here was someone writing down names and describing problems that I had a vague unease about, but was too inexperienced to really articulate or do something about. Typically the refactorings address the same kind of issues that a code review with a skilled experienced programmer would address. Long parameter lists, too long methods, objects delving about in each others private variables, case statements, related code spread across different objects etc. None of these problems are debiliting in themselves, but added up, they lead to software that can be prone to error and difficult to maintain.

Most of the remaining substance of the book, 209 pages, is given over to a taxonomy of refactorings. These 72 refactorings are covered in detail with comprehensive simple examples presented in Java. Each refactorings is given a clear name, a number and a line or two of descriptive text. The motivation for the refactoring is then discussed, often including caveats and cautions. The mechanics of implementing the refactoring are then listed, with 1 or more (and often more) examples of implementing the refactoring. Refactorings range from the very simple to more complex examples such as Convert Procedural Design to Objects.

Due to the difficulties of reproducing large and complex sections of code, Fowler sticks with relatively simple examples. These seem to grate on him more than the reader, and he can come across as somewhat embarrassed when we look at the employee, programmer, manager pay example for the tenth time. I certainly didn't have a problem with it though.

Conclusion

This is a very well written and fun to read book. I personally feel that much of the material is implied by from Code Complete, but Fowler does a fantastic job of expanding and formalizing the idea of applying explicit refactorings. Much like Code Complete gave a motivation for keeping code well commented and laid out, this book presents the case for care and feeding of how to structure software. To fight bitrot and technical debt, poorly structured and unclear code should be targetted and refactored to improve structure and clarity. This gives a very real payback in terms of less required maintenance, and ease in adding features later on down the line.

Despite the fact that all the examples are in Java, the ideas are easily transferable to C++ or any procedural object oriented language.

Highly recommended."
Software

Submission + - Sage wins Award for Free Mathematical Software

Submitted by
Ponca City, We Love You
Ponca City, We Love You writes: "Since 2003, Cetril has organised the Trophées du Libre contest to reward innovative free software and this year Sage won first place in the Scientific Software category. Sage faced initial skepticism from the mathematics and education communities. "I've had a surprisingly large number of people tell me that something like Sage couldn't be done — that it just wasn't possible," said William Stein, lead developer of the tool. "I'm hearing that less now." The big commercial programs — Matlab, Maple, Mathematica and Magma — charge license fees. The Mathematica Web page, for example, charges $2,495 for a regular license. But the frustrations aren't only financial. Commercial programs don't always reveal how the calculations are performed. This means that other mathematicians can't scrutinize the code to see how a computer-based calculation arrived at a result. "Not being able to check the code of a computer-based calculation is like not publishing proofs for a mathematical theorem," Stein said. "It's ludicrous.""
NASA

Submission + - NASA to scientists: Reveal sex history or lose job 1

Submitted by
Markmarkmark
Markmarkmark writes: "Wired is reporting that all NASA JPL scientists must 'voluntarily' (or be fired) sign a document giving the government the right to investigate their personal lives and history 'without limit'. According to the Union of Concerned Scientists this includes snooping into sexual orientation, mental & physical health as well as credit history and 'personality conflict'. 28 senior NASA scientists and engineers, including Mars Rover team members, refused to sign by the deadline and are now subject to being fired despite a decade or more of exemplary service. None of them even work on anything classified or defense related. They are suing the government and documenting their fight for their jobs and right to personal privacy."
Space

Submission + - Earth's Evil Twin (esa.int)

Submitted by
Riding with Robots
Riding with Robots writes: "For the past two years, Europe's Venus Express orbiter has been studying Earth's planetary neighbor up close. Today, mission scientists have released a new collection of findings and amazing images. They include evidence of lightning and other results that flesh out a portrait of a planet that is in many ways like ours, and in many ways hellishly different, such as surface temperatures over 400C and air pressure a hundred times that on Earth."

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