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Jumat, 10 April 2009

The MacBook Air-Dell Adamo Deathmatch

Two laptops: One's a Mac, one's a PC. Which is better? PC World takes both notebooks and stages a computer kumite to make a few quick calls

The Tale of the Tape

You know all about the on-again, off-again PC-Mac turf war, of course. Which is better? One thing we can tell you is that PC makers sure are taking note of Apple's awesome design work. And that's the setup for the welterweight matchup we have going on today.

In this corner (pictured at right), the MacBook Air, the sleek standard-bearer for how Apple does computing. In the other, the Dell Adamo, the spunky up-and-comer that packs on ports…and takes some not-so-subtle jabs at the big "A."

Neither company really positions its ultraslim ultraportable as a high-performance hot rod. Heck, both of them eschew optical drives to stay lean and mean. But they're both expensive--very, very expensive. We figured it was time to find out if either the Air or the Adamo has what it takes to win.

Now before these two palookas start mixing it up, let's look at what they each bring to tonight's fight. The MacBook Air is the cagey vet. Since it first showed up on the scene, it has improved its game by providing better processors and an honest-to-goodness graphics card, nVidia's GeForce 9400M. That means it can actually play some games--not many, but some.

The Air we last reviewed offered a 1.86GHz Core 2 Duo CPU and 2GB of RAM, and scored a 78 in WorldBench 6. In our battery-life tests, the Air survived for about 2.5 hours before sputtering out. It can accommodate a 120GB hard disk (our more-expensive model came with a 128GB solid-state drive). But then, of course, there's also the dreaded "Apple Tax": These machines range in price from $1799 to $2499.

The Dell Adamo, on the other hand, offers lesser parts and…charges…more? Really? Let's go over this. Dell's high-style PCs cost between $1999 and $2699. The Adamo maxes out at a 1.4GHz CPU but compensates with 4GB of RAM to handle a 64-bit version of Windows Vista Home Premium. Supposedly its battery will last 5 hours in tests, if we're to believe promotional materials. Will it get slapped around in our WorldBench 6 suite? Stay tuned; we'll update this story as soon as we receive results from our labs. For now, though, buckle up for a feature-by-feature smackdown.

Hey, you two silicon status symbols: Are you ready to rumble? FIGHT!

Rabu, 08 April 2009

Hard disk drive


HDDs record data by magnetizing ferromagnetic material directionally, to represent either a 0 or a 1 binary digit. They read the data back by detecting the magnetization of the material. A typical HDD design consists of a spindle which holds one or more flat circular disks called platters, onto which the data are recorded. The platters are made from a non-magnetic material, usually aluminum alloy or glass, and are coated with a thin layer of magnetic material. Older disks used iron(III) oxide as the magnetic material, but current disks use a cobalt-based alloy.[citation needed]

A cross section of the magnetic surface in action. In this case the binary data is encoded using frequency modulation.

The platters are spun at very high speeds. Information is written to a platter as it rotates past devices called read-and-write heads that operate very close (tens of nanometers in new drives) over the magnetic surface. The read-and-write head is used to detect and modify the magnetization of the material immediately under it. There is one head for each magnetic platter surface on the spindle, mounted on a common arm. An actuator arm (or access arm) moves the heads on an arc (roughly radially) across the platters as they spin, allowing each head to access almost the entire surface of the platter as it spins. The arm is moved using a voice coil actuator or in some older designs a stepper motor.

Older drives read the data on the platter by sensing the rate of change of the magnetism in the head; these heads had small coils, and worked (in principle) much like magnetic-tape playback heads, although not in contact with the recording surface. As data density increased, read heads using magnetoresistance (MR) came into use; the electrical resistance of the head changed according to the strength of the magnetism from the platter. Later development made use of spintronics; in these heads, the magnetoresistive effect was much greater than in earlier types, and was dubbed "giant" magnetoresistance (GMR). This refers to the degree of effect, not the physical size, of the head — the heads themselves are extremely tiny, and are too small to be seen without a microscope. GMR read heads are now commonplace.[citation needed]

HD heads are kept from contacting the platter surface by the air that is extremely close to the platter; that air moves at, or close to, the platter speed.[citation needed] The record and playback head are mounted on a block called a slider, and the surface next to the platter is shaped to keep it just barely out of contact. It's a type of air bearing.

The magnetic surface of each platter is conceptually divided into many small sub-micrometre-sized magnetic regions, each of which is used to encode a single binary unit of information. In today's HDDs, each of these magnetic regions is composed of a few hundred magnetic grains. Each magnetic region forms a magnetic dipole which generates a highly localized magnetic field nearby. The write head magnetizes a region by generating a strong local magnetic field. Early HDDs used an electromagnet both to generate this field and to read the data by using electromagnetic induction. Later versions of inductive heads included metal in Gap (MIG) heads and thin film heads. In today's heads, the read and write elements are separate, but in close proximity, on the head portion of an actuator arm. The read element is typically magneto-resistive while the write element is typically thin-film inductive.[6]

In modern drives, the small size of the magnetic regions creates the danger that their magnetic state might be lost because of thermal effects. To counter this, the platters are coated with two parallel magnetic layers, separated by a 3-atom-thick layer of the non-magnetic element ruthenium, and the two layers are magnetized in opposite orientation, thus reinforcing each other.[7] Another technology used to overcome thermal effects to allow greater recording densities is perpendicular recording, first shipped in 2005,[8] as of 2007 the technology was used in many HDDs.[9][10][11]

Modern drives also make extensive use of Error Correcting Codes (ECCs), particularly Reed–Solomon error correction. These techniques store extra bits for each block of data that are determined by mathematical formulas. The extra bits allow many errors to be fixed. While these extra bits take up space on the hard drive, they allow higher recording densities to be employed, resulting in much larger storage capacity for user data. [12]

See File System for how operating systems access data on HDDs and other storage devices.

[edit] Architecture

A hard disk drive with the platters and spindle motor hub removed showing the copper colored stator coils surrounding a bearing at the center of the spindle motor. The orange stripe along the side of the arm is a thin printed-circuit cable. The spindle bearing is in the center.

A typical hard drive has two electric motors, one to spin the disks and one to position the read/write head assembly. The disk motor has an external rotor attached to the platters; the stator windings are fixed in place. The actuator has a read-write head under the tip of its very end (near center); a thin printed-circuit cable connects the read-write head to the hub of the actuator. A flexible, somewhat 'U'-shaped, ribbon cable, seen edge-on below and to the left of the actuator arm in the first image and more clearly in the second, continues the connection from the head to the controller board on the opposite side.

The head support arm is very light, but also rigid; in modern drives, acceleration at the head reaches 250 Gs.

Opened hard drive with top magnet removed, showing copper head actuator coil (top right).

The silver-colored structure at the upper left of the first image is the top plate of the permanent-magnet and moving coil motor that swings the heads to the desired position (it is shown removed in the second image). The plate supports a thin neodymium-iron-boron (NIB) high-flux magnet. Beneath this plate is the moving coil, often referred to as the voice coil by analogy to the coil in loudspeakers, which is attached to the actuator hub, and beneath that is a second NIB magnet, mounted on the bottom plate of the motor (some drives only have one magnet).

The voice coil, itself, is shaped rather like an arrowhead, and made of doubly-coated copper magnet wire. The inner layer is insulation, and the outer is thermoplastic, which bonds the coil together after it's wound on a form, making it self-supporting. The portions of the coil along the two sides of the arrowhead (which point to the actuator bearing center) interact with the magnetic field, developing a tangential force that rotates the actuator. Current flowing radially outward along one side of the arrowhead, and radially inward on the other produces the tangential force. (See magnetic field#Force on a charged particle.) If the magnetic field were uniform, each side would generate opposing forces that would cancel each other out. Therefore the surface of the magnet is half N pole, half S pole, with the radial dividing line in the middle, causing the two sides of the coil to see opposite magnetic fields and produce forces that add instead of canceling. Currents along the top and bottom of the coil produce radial forces that do not rotate the head.

Selasa, 31 Maret 2009

The iPhone's Untapped Potential

Apple is known for its innovative gadget design, and with the release of the iPhone, it continues to live up to its hype. But while people are fawning over features like the smart, multitouch screen and the advanced Web browser, there is important technology under the hood that will likely go underappreciated. The iPhone has tiny, powerful sensors--an accelerometer, an ambient light sensor, and an infrared sensor--that are able to pick up cues from the environment and adjust the phone's functions accordingly. Apple has decided to use these sensors for detecting when to convert the screen view from portrait to landscape, for adjusting the brightness of the screen based on the brightness of the environment, and for disabling the touch screen when a person holds the phone to her ear.

Of course, Apple isn't the first to put sensors such as accelerometers in phones. Nokia, for example, has a sports phone (called the 5500) that uses an accelerometer as a pedometer. When a person takes the phone jogging, the accelerometer logs the rate of vibrations and sends that data to software that determines speed and distance. The 5500 also offers an accelerometer-based game in which a user tilts the device to navigate a ball through a maze. In addition, Nokia offers a developers' kit so that people can make their own accelerometer-based games, potentially mimicking the style of those played with Nintendo's popular Wii controller.

These functions, while useful and entertaining, are still pretty mundane, a research scientist at MIT. "These are trivial uses for what has the potential to provide a whole slew of new features and functionality," he says. Separate research taking place at MIT, Intel, and other companies suggests that, with the right software, built-in hardware such as accelerometers, light sensors, a GPS, and the phone's own microphone could provide contextual clues about people's activities and behaviors. A sensor-enabled phone could feasibly help monitor your exercise habits, keep track of an elderly relative's activities, and let your friends and family know if you're available for a call or instant-messaging conversation. It could even provide insight into social networks.

"If you get access to [a phone's] accelerometer data, you can get a variety of contextual clues about how the user is living their life," Eagle says--for instance, whether or not a user is riding a bike, taking the subway, walking up stairs, or sitting for a long period of time. The data can be used to let workers know if they need to take a break or if a person is meeting exercise goals, he says. Eagle and professor of media arts and sciences at MIT, have used Nokia phones equipped with sensors to study the behavior of people in groups and even predict their actions to a certain extent.

To explore other possibilities, researchers at Intel use a small gadget, about the size of a pager, that amasses data from seven sensors: an accelerometer, a barometer, a humidity sensor, a thermometer, a light sensor, a digital compass, and a microphone, a researcher . Most of the sensors are used to determine location and activity, but the microphone can provide interesting insight into social networks, she says, such as whether a person is having a business conversation or a social chat. Aware of privacy concerns, the researchers designed the microphone data to be immediately processed so that all words are removed, and only information about tone, pitch, and volume is recorded. Recently, Intel researchers equipped a first-year class of University of Washington graduate students with these sorts of sensors and, based on their interactions, were able to watch social networks develop over time.

Jumat, 27 Maret 2009

Citroën C5 2.7 HDI V6

The mention of the name "C5" in a vehicular context is unlikely to prompt thoughts of sumptuous ease in anyone who is over 35. Instead, the image that will almost certainly spring to mind is of the Sinclair C5, the 80s electric tricycle that became a comic byword for bad design.

Rest assured, that C5 did not have a back massager, though anyone foolhardy enough to squeeze into one could have done with a little muscular manipulation.

The Citroën C5, by contrast, does have a back massager, as well as heated seats. I didn't realise this on my first drive. Running late to meet a friend, I didn't at first take much notice of the pleasurable warmth around my bottom. Nor did I immediately appreciate the undulating sensation in the small of my back. But gradually I became aware of the rhythmic movement, as it crept up on me like Górecki's Third Symphony or a furtive masseuse. After a while I began to wonder what that dull pressure was on my spine and why my bum was so hot.

Was this it? Was I finally experiencing the nervous breakdown I've spent years working towards? If so, then it was not unpleasant. Indeed, if you were thinking of having a nervous breakdown, I'd recommend the C5 as an ideal venue to ameliorate the harsher physical manifestations of personal crisis.

In fact, once you get used to the slightly odd automatic gear stick, I'd wager that it would be a stiff challenge to crack up in this C5. OK, you've made a mess of your private life, but just feel that smooth leather. Your career is going nowhere. Too bad, but check out the leg room. No one likes you - know that feeling, still, that pneumatic suspension is a joy to behold.

While Francophiles have plenty to choose from among hatchbacks and smaller cars, it's been a while since Citroën produced a classy larger model of any repute. And you'd have to go back all the way to the DS, with its distinctive, long bonnet, to a time when Citroën led the field.

The C5 is a self-conscious attempt to loosen the forearm nelson in which the German motor industry has the higher-end saloon market so effectively locked. Citroën even boasts of its "Teutonic-like levels of quality", which amounts to a public acknowledgment of what the public already believes - that the Germans do it better.

But in this case the French have produced something that in comfort, if perhaps not performance, rivals an Audi or BMW. While it may not possess the iconic appeal of the DS, the C5 is undoubtedly handsome. If that doesn't massage the ego, then just feel what it can do for your back.

Citroën C5 2.7 HDI V6

Price £24,395
Top speed 139mph
Acceleration 0-62 in 9.6 seconds
Average consumption 33.6mpg
CO2 emissions 223g/km
Eco rating 5/10
At the wheel Sebastian Faulks
Bound for The Dordogne
In a word Teutonique

Tough task: Designing a game about your 'first time'

SAN FRANCISCO, California-- In an industry dominated by men, leave it to women to come up with the winning idea in a contest to create a concept for a video game about losing one's virginity.

Two women won a contest this week to create a concept for a video game about losing one's virginity.

Two women won a contest this week to create a concept for a video game about losing one's virginity.

On Wednesday, at the Game Developers Conference here, the two-woman team of Heather Kelley and Erin Robinson won the Game Design Challenge with just 36 hours of preparation, while their competitors had weeks to come up with concepts for a game about "your first time."

This was the sixth straight year of the design challenge, hosted annually by New York-based game developer Eric Zimmerman. The contestants are generally top-tier game designers like two-time winner and Spore and The Sims creator Will Wright, Deus Ex lead designer Harvey Smith, or 2008 winner and Leather Goddesses of Phobos creator Steve Meretzsky.

The contestants are generally given several weeks to come up with a concept for a game based on some sort of unusual challenge posed by Zimmerman. Past themes have included a game about love, a game based on the poetry of Emily Dickinson, and a game that could win the Nobel Peace Prize.

"We are in a medium that is just incredibly plastic," Zimmerman said. "We can put anything up on the screen...Still, we find every year that most of the money being put into games is put into a relatively narrow (set of) genres" that tends to include monsters, dragons, and the like.

Zimmerman added that the purpose of the challenge is "to think about how we can create games that really break away" from what's been done so many times before.

Don't Miss Sex and autobiography have been constant themes in literature, film, and theater, Zimmerman argued, pointing to "Lolita," the work of Henry Miller, Chaim Potok's novel, "My name is Asher Lev," and the films of Fellini and Woody Allen.

But while Zimmerman touted the widespread historical acceptance of the theme of autobiographical sex, he noted with some dismay that veteran game designer Kim Swift, who works for Valve and who created the award-winning Portal, had originally been slated to be among the contestants but had eventually been pressured by Valve to withdraw due to the theme.

"I'm saying this as a fan of Valve," Zimmerman said, "but I do find it frustrating and disturbing that Kim would be pulled from the panel."

Still, he said, after word got around about Swift's withdrawal, Lapis designer Kelley and independent developer Robinson volunteered to step up and compete.

The two ended up facing off against Meretzsky, on hand to defend his crown, and Habbo Hotel lead designer Sulka Haro.

And in the end, while all three submissions were well-received, the duo of Kelley and Robinson were judged by the audience to have very closely beaten out Meretzsky.

The two women came up with a concept for "Our first times," and presented it as a two-level game, one level for Kelley's experience and the other for Robinson's. They imagined a series of mini games that could be played on Nintendo's Wii, or possibly on Apple's iPhone.

Kelley began by explaining that her game would commence with the player having to pick an outfit for a date that was intended to conclude with their deflowering. It would have to be the least complicated outfit possible, she said, nothing with zippers that get stuck, or too many buttons or ties.

Then, there would be a mini game in which players would have to shave their legs, making especially sure not to miss the all-important spot "by the knees." Next up, dinner, and making sure to remove all the garlic from the meals, something the main character--clearly a female, since the game was presented from a woman's perspective--would have to do because of the general cluelessness of the boyfriend in question.

The next mini game would revolve around choosing the proper mood music from a selection of LPs--yes, records, since the game would be set in the timeframe of Kelley's first time. And clearly, she said, Miles Davis would have to be the choice.

The penultimate mini game would task the player with "not falling off the top bunk" in a college dorm room," while the final task would involve flicking off the smirking roommate.

The Robinson level also involved a series of mini games that commenced with "driving home from ultimate-Frisbee practice" and setting the radio station in a car--perhaps using the Wiimote dial, she said--to anything except country music. Next would be a stop at a drug store to buy a brand of condoms that doesn't terrify you, and then going "back to his place," and grappling with adjusting the tracking on his "antiquated" VCR.

Being a game concept presented from the woman's perspective, the next mini game would revolve around "making the first move. Poor guy."

And then, afterward, calling the best friend to tell the tale.

"But you have to be careful," Robinson said, "because she's next to mom and grandma on the speed dial."

Perhaps given their short notice, the mini-game concepts created by Kelley and Robinson weren't very fleshed out, something that was a shame since they seemed to be onto something. But the crowd appreciated how much effort they had put into the storyboards they'd created, and forgave the rudimentary fleshing out of the details.

Meretzsky's concept--which came in a very close second--ended up revolving around the idea of moving beyond the awkwardness of fumbling high school attempts at romance. But before explaining his final design, he talked at length about the challenges of coming up with a game idea when every possible title was too overtly sexual. He said he tried out "Where's dildo," but discarded it because "it had nothing to do with my autobiography."

And then, he thought "about the almost too obvious genre of first-person shooters."

He also threw away "Call of Booty"--because it would have "problems that would keep it off the shelf at Wal-Mart"--and then almost settled on a beat-matching idea called "Hump Hump Revolution."

And, playing off the title of Swift's hit game, as well as a popular 2008 film, he said he nearly ended up with "Zack & Miri make a Portal," but "my business people tell me paying licenses for two different (intellectual properties) is a non-starter."

In the end, he said, he came up with a three-act structure for a game based in the virtual world, Second Life, where act one involves the awkward era of high school, the second act is the more promising college years and finally, act three, happiness in the form of a series of vignettes including dates, a wedding, and then, home life.

The game, he said, would be called, "Wait, time passes."

"No matter how picked on you are," Meretzsky said, "this too shall pass. Your time will come, and you will find happiness and your place in the world."

Of the six Game Design Challenges, this year's felt the most wanting for detail and working game mechanics. That may have been because the contestants' task of building something autobiographical didn't meld well with game design. Still, the crowd, which was heavy with game designers, appreciated the efforts and shouted out their support for all three contestants.

After all, in the end, the point was to take a particularly challenging game design topic and create something that could plausibly be a working title. And who would know better the difficulties of doing so than a room full of game designers?

Study: Technology can overwhelm even 20-somethings

WASHINGTON (AP) — They are comfortable with gadgets, yet shudder sometimes as the cell phone rings.

This group — primarily male and in their late 20s — is called the "Ambivalent Networkers" in a study released Wednesday by the Pew Internet and American Life Project. Pew found this group notable because its members have lived with the Internet and other technologies for much of their lives.

In the study, Pew examined American adults' gadgets and services, their activities and their attitudes toward technology. About 60 percent of the overall respondents didn't have significant attachments to mobile devices, either because they didn't have such gadgets or because they were fine with desktop PCs.

But nearly 40 percent did say they were glued to their mobile devices. And the Ambivalent Networkers make up a fifth of that group.

"They're the most active on social networks and using mobile devices for a range of activities, yet they think it's a good idea to take a break," said John Horrigan, Pew's associate director for research. "They are not thrilled about all that's available."

These people aren't willing to go off the grid, either, said Lee Rainie, Pew's director. Their friends, family and co-workers are all connected by technology, and they fear they'd miss out if they check out.

Technology, to them, "feels like an obligation," Rainie said.

Another one-fifth of the mobile-attached users feel quite differently. These people, according to Pew, are the "Digital Collaborators." They not only are comfortable with technology, but they also are enthusiastic. They also tend to be male, but in their late 30s.

Horrigan said Digital Collaborators more likely have elevated into jobs that require collaboration across distance.

"The live a professional lifestyle that draws them to digital resources," he said. "They are lunging ahead with less fear and hesitation."

The Pew analysis was based on surveys taken in late 2007 of 3,553 adult Americans. The surveys have a margin of sampling error of plus or minus 2 percentage points.

Kamis, 26 Maret 2009

The multi-touch controls familiar to Apple iPhone users will be built-in to Microsoft's Windows 7.

Windows Touch will be a "first class way to interact with your PC alongside mouse and keyboard," said the firm.

Microsoft believes multi-touch PCs will become popular in retail, public spaces, on laptops and "kitchen PCs".

Some Windows machines already feature rudimentary touch input and Apple is also reportedly adding touch for displays in its Snow Leopard OS update.

A small number of multi-touch PCs are already on the market, including the HP TouchSmart and the Dell Latitude XT, and Microsoft hopes Windows 7 will create a new ecosystem of devices that take advantage of touch.

The latest generation of Apple's laptops also feature a glass trackpad that supports multi-touch gestures.

Microsoft has launched a Windows Touch Logo program, which will help consumers understand if a machine has been optimised for the new control system.

Windows Touch will features controls such as tap and double tap, drag, scroll, zoom, flick and rotate.

In a posting on the Windows 7 engineering blog, the team leading Touch developments said: "Quite a few folks have been a little sceptical of touch, often commenting about having fingerprints on their monitor or something along those lines.

Lessons learned

"We think touch will become broadly available as the hardware evolves."

Windows Touch is incorporating many of the lessons learned from the development of Microsoft's Surface table computer.

Microsoft shows off Windows Touch

Microsoft user interface evangelist Chris Bernard told BBC News: "Windows 7 will help take touch into the mainstream.

"While Surface and machines running Windows 7 are different devices we have evolved a common vocabulary of touch.

"Gesture and touch are the two biggest changes to how we interact with our computers since the launch of the first Graphical User Interface, and the use of the keyboard and mouse."

Microsoft says Windows Touch will be much more than just a "touch shell" for Windows.

"We made sure you are getting the full Windows 7 experience," the blog post said.

While some applications will be optimised for touch, such as Internet Explorer and Windows Media Centre, programs which are "touch unaware" will also have some level of touch control.

"For example, if someone tries touch scrolling over a window that is touch unaware, we can detect the presence of various types of scrollbars and scroll them," the engineers said.

To help optimise the different ways of touching and gesturing Microsoft said it analysed data from "thousands of samples from hundreds of people".

Windows 7 is expected to be released at the start of 2010. A "release candidate" for users to try out will be available at the end of May.