Howstuffworks "What are superdelegates?" [Politics]

With the Democratic nomination going on as long as it has and more and more talk of the 'Superdelegates', I wanted to know What superpowers they hold?
Turns out they're regular humans...bummer. They do have the power to turn a nomination around 180.
~P

Howstuffworks "What are superdelegates?"

What are superdelegates?

by Josh Clark

What are superdelegates?

When the 2008 campaign for president began, it wasn't such a big story that there would be superdelegates at the 2008 Democratic National Convention in Denver, Colo. Superdelegates have been at every convention since they were created through Democratic National Committee (DNC) rules in 1982 [source: CNN]. In previous contests, superdelegates haven't enjoyed much of the spotlight. But as the Democratic primaries whittled down the number of competitors for the nomination, a close race emerged between Senators Hillary Clinton and Barack Obama. The two candidates are neck and neck for the Democratic Party's nomination for president of the United States, even after scores of primaries and caucuses, including those on Super Tuesday -- a day designed to establish a clear front-runner.

Presidential Primaries Image Gallery

Ben Sklar/Getty Images
The close race between Senators Hillary Clinton and Barack Obama (shown at a debate in Texas) in the 2008 primaries caused concern over the role superdelegates would play in choosing the party's nomination. See more presidential primaries images.

As the delegate counts for Clinton and Obama stay close, it's clear that in the 2008 primary season, superdelegates will have a huge impact on which candidate the Democrats nominate for the run for the presidency. Some Democrats have publicly pledged to leave the party if superdelegates don't follow the popular vote. "If the Democratic Party does not nominate the candidate … that the majority (or plurality) of its participants in primaries and caucuses want it to nominate, then I will quit the Democratic Party," writes Chris Bowers, a member of the Pennsylvania State Democratic Committee. [source: Open Left].

The term "smoke-filled room" came back into vogue to describe the shady type of politics in which superdelegates could potentially engage [source: NPR]. This image reminds us of politics before Progressive Era reforms, where an elite few could choose the candidate they wanted, rather than the one chosen by the people.

In the 2008 primary season, the idea that Democratic superdelegates could use their status to choose a candidate, rather than supporting the one ahead in the popular vote, places them under intense public scrutiny and political pressure.

What is it about superdelegates that have some people so thoroughly steamed? Find out on the next page.­ ­

Superdelegate Votes

To win the 2008 Democratic Party nomination for president, a candidate must rack up 2,025 delegates. These delegates are won through votes from state primaries or caucuses. Generally, delegates are awarded by percentage in Democratic nominating contests; this is in contrast to some Republican contests, which are winner-take-all. So if one Democratic candidate wins 60 percent of the popular vote in a state that offers 10 delegates, for example, that candidate will win six delegates in that state. This continues state by state, and usually one candidate manages to rack up a clear majority of the delegates before the convention.

Delegates won in primaries and caucuses are considered pledged voters, meant to represent the will of the people who voted for a particular candidate. At the national convention, these delegates are expected to vote for the candidate chosen by the thousands of voters they represent. This is not the case with superdelegates.

In the 2008 primary, there are about 800 superdelegates, making up around 20 percent of the delegate count for the Democratic Party [source: CNN]. These superdelegates are Democratic members of Congress, high-ranking members of the Democratic Party, state governors and former presidents and vice presidents [source: NPR].

Superdelegates are simply "unpledged voters." Their vote represents the their own choice, rather than the wishes of the voters, and these unpledged delegates can pledge their votes as they see fit.

Superdelegates have to consider how to use their votes carefully. They may:

• Vote in step with how the voters in the majority of states voted
• Vote in line with Democratic voters nationwide
• Vote in favor of the candidate with the most pledged delegates, even if it is just a slim majority.

A superdelegate can also choose to vote his or her "conscience." This is one way of saying that a superdelegate may not vote the way the majority of voters do, but on the candidate he or she feels is best. "Superdelegates are supposed to vote their conscience and supposed to vote for [the] person they think would make the best candidate and the best president," Howard Wolfson of Hillary Clinton's campaign said in February 2008 [source: Miami Herald].

Since they remain unpledged, superdelegates are also allowed to switch their pledges from one candidate to another -- long before the national convention. This seems to be especially allowable when a superdelegate rescinds his or her pledge based on his or her constituency. In the 2008 primaries, Georgia Rep. David Scott changed his pledge from Sen. Hillary Clinton to Sen. Barack Obama. Around 80 percent of the Democratic voters in Scott's district voted for Obama, and Scott changed his pledge [source: AP].

Diana Walker/Time Life Pictures/Getty Images
Former Vice President Walter Mondale (shown in July 1984) was boosted to the 1984 Democratic Party nomination by superdelegates.

Superdelegates had an almost immediate effect after their creation in 1982. At the 1984 convention -- thanks to superdelegate votes -- Vice-President Walter Mondale won the nomination over rival Sen. Gary Hart, who had won more states than Mondale (although Mondale won more of the popular vote) [source: The New York Times]. It appears that they may have an even more striking influence in the 2008 primaries.

Read about why superdelegates may be a good thing -- or could cripple the democratic process -- on the next page.

Superdelegate Pros and Cons

What's the point of having superdelegates in the first place? Explains Willie Brown, former mayor of San Francisco, "You have superdelegates because … You don't want bleed-over from the Green Party, the independents and others in deciding who your nominee will be" [source: CNN]. Brown cites the ability of undeclared or non-Democrat voters in some states to cast a vote in Democratic primaries or caucuses. The logic follows that if enough of these nonaffiliated voters cast ballots, voters outside the Democratic Party could decide the nominee.

Adding superdelegates to the convention provides a countermeasure against such an event. Since superdelegates are all registered Democrats (and usually elected officials), it's reasonable to assume they wouldn't vote contrary to Democratic Party lines.

But to some, the power superdelegates have to sway a nomination seems to fly in the face of a democratic process. "If the superdelegates go against the popular will of the voters, whoever emerges as 'victor' will enter the presidential election shorn of democratic legitimacy and devoid of electoral credibility" warned columnist Gary Younge during the 2008 race [source: Guardian].

Robyn Beck/AFP/Getty Images
Delegates at the 2004 Democratic National Convention in Boston, Mass.

Superdelegates have one vote for one person; those pledged delegates that are earned through primaries can represent thousands of individuals. This leads to concerns about the disproportionate influence a superdelegate can wield. While individual voters' votes are ostensibly earned through a candidate's platform and rhetoric, a superdelegate's vote can, according to DNC rules, technically be bought.

Some political observers are concerned over the rules covering the courting of superdelegates. There is little if any protocol that says delegates can't be given outright gifts or even money. By the time the 2008 primary season began, some already had received money in the form of campaign contributions [source: Boston Globe]. "A candidate can feel free to entice a superdelegate with allusion to past and future favors," added one reporter [source: NPR].

Not all in the Democratic Party are upset about the existence of superdelegates. Democratic strategist Tad Devine suggests that superdelegates are a necessary part of the Democratic nominating process, but not until the convention. Devine laments the accrual of superdelegates' pledged votes beginning early on in the 2008 primary season. "The superdelegates were never intended to be part of the dash from Iowa to Super Tuesday and beyond," writes Devine. "If the superdelegates determine the party's nominee before primary and caucus voters have rendered a clear verdict, Democrats risk losing the trust that we are building with voters today" [source: The New York Times].

Tim Walz, a superdelegate in the 2008 primary, sees superdelegates in much the same way. "Let's just let the people make up their mind and we'll cast our votes according to that" [source: NPR].

Of course, it's not entirely fair that superdelegates took all of the heat in the close 2008 primary season. Even the delegates won in primaries and caucuses aren't actually bound to vote the way they've pledged to [source: Politico].

For more information on politics and other related topics, visit the next page.

Lots More Information

Related HowStuffWorks Articles

• How the Electoral College Works
• How Political Conventions Work
• How Political Primaries Work
• How do caucuses work?
• Why is Super Tuesday so super?
• How Barack Obama Works
• How Hillary Clinton Works

More Great Links

• 2008 Superdelegate Endorsement List (Unofficial)
• Democratic National Committee
• Move On's Online Superdelegate Petition

New Look at Death Sentences and Race - New York Times [Legal][Interesting]

This is been going on unchecked for so long and so many people have lost their lives. Its sickening.

 ~P

New Look at Death Sentences and Race - New York Times

---

April 29, 2008

Sidebar

New Look at Death Sentences and Race

By ADAM LIPTAK

About 1,100 people have been executed in the United States in the last three decades. Harris County, Tex., which includes Houston, accounts for more than 100 of those executions. Indeed, Harris County has sent more people to the death chamber than any state but Texas itself.

Yet Harris County's capital justice system has not been the subject of intensive research — until now. A new study to be published in The Houston Law Review this fall has found two sorts of racial disparities in the administration of the death penalty there, one commonplace and one surprising.

The unexceptional finding is that defendants who kill whites are more likely to be sentenced to death than those who kill blacks. More than 20 studies around the nation have come to similar conclusions.

But the new study also detected a more straightforward disparity. It found that the race of the defendant by itself plays a major role in explaining who is sentenced to death.

It has never been conclusively proven that, all else being equal, blacks are more likely to be sentenced to death than whites in the three decades since the Supreme Court reinstated the death penalty in 1976. Many experts, including some opposed to the death penalty, have said that evidence of that sort of direct discrimination is spotty and equivocal.

But the author of the new study, Scott Phillips, a professor of sociology and criminology at the University of Denver, found a robust relationship between race and the likelihood of being sentenced to death even after the race of the victim and other factors were held constant.

His statistics have profound implications. For every 100 black defendants and 100 white defendants indicted for capital murder in Harris County, Professor Phillips found that an average of 12 white defendants and 17 black ones would be sent to death row. In other words, Professor Phillips wrote, "five black defendants would be sentenced to the ultimate sanction because of race."

Scott Durfee, the general counsel for the Harris County district attorney's office, rejected Professor Phillips's conclusions and said that district attorneys there had long taken steps to insulate themselves from knowing the race of defendants and victims as they decided whether to seek the death penalty.

"To the extent Professor Phillips indicates otherwise, all we can say is that you would have to look at each individual case," Mr. Durfee said. "If you do that, I'm fairly sure that you would see that the decision was rational and reasonable."

Indeed, the raw numbers support Mr. Durfee.

John B. Holmes Jr., the district attorney in the years Professor Phillips studied, 1992 to 1999, asked for the death sentence against 27 percent of the white defendants, 25 percent of the Hispanic defendants and 25 percent of the black defendants. (Professor Phillips studied 504 defendants indicted for the murders of 614 people. About half of the defendants were black; a quarter each were white and Hispanic.)

Mr. Holmes was, Professor Phillips said, selective but effective: he asked for the death sentence against 129 defendants and obtained 98.)

But Professor Phillips said that the numbers suggesting evenhandedness in seeking the death penalty did not tell the whole story. Once the kinds of murders committed by black defendants were taken into consideration — terrible, to be sure, but on average less heinous, less apt to involve vulnerable victims and brutality, and less often committed by an adult — "the bar appears to have been set lower for pursuing death against black defendants," Professor Phillips concluded.

Professor Phillips wrote about percentages and not particular cases, but his data suggest that black defendants were overrepresented in cases involving shootings during robberies, while white defendants were more likely to have committed murders during rapes and kidnappings and to have beaten, stabbed or choked their victims.

When the nature of the crime is taken into account, Professor Phillips wrote, "the odds of a death trial are 1.75 times higher against black defendants than white defendants." Harris County juries corrected for that disparity to an extent, so that the odds of a death sentence for black defendants after trial dropped to 1.49.

Jon Sorensen, a professor of justice studies at Prairie View A&M University in Texas, said he was suspicious of Professor Phillips's methodology.

"It's bizarre," Professor Sorensen said. "It starts out with no evidence of racism. Then he controls for stuff."

Moreover, Professor Sorensen said, Professor Phillips failed to take account of other significant factors, including the socioeconomic status of the victims.

Professor Sorensen said he remained convinced that racial disparities, if they exist at all, "are victim-based only," as earlier studies have found.

This discussion, at least where the courts are concerned, is entirely academic. Twenty-one years ago, the Supreme Court ruled that even solid statistical evidence of racial disparities in the administration of the death penalty did not offend the Constitution. The vote was 5 to 4, and the case was McCleskey v. Kemp.

That ruling closed off what had seemed to opponents of the death penalty a promising line of attack, and they are still furious about it, comparing it to the court's infamous 1857 decision that blacks slaves were property and not citizens.

"McCleskey is the Dred Scott decision of our time," Anthony G. Amsterdam, a law professor at New York University, said in speech last year at Columbia.

"It is a decision for which our children's children will reproach our generation and abhor the legal legacy we leave them," said Professor Amsterdam, who worked on the McCleskey case and many other capital punishment landmarks.

The majority opinion in McCleskey was written by Justice Lewis F. Powell Jr. After he retired, his biographer asked Justice Powell whether, given the chance, he would change his vote in any case.

"Yes," Justice Powell said. "McCleskey v. Kemp."

Howstuffworks "Who was the real Count Dracula?" [Interesting][History]

Howstuffworks "Who was the real Count Dracula?"

Who was the real Count Dracula?

by Josh Clark

Who was the real Count Dracula?

It wasn't until he came across documents during his research at the British Museum that novelist Bram Stoker found the man who would serve as the perfect foundation for his classic gothic horror character, Count Dracula [source: Kent State University]. Vlad Tepes (pronounced te'-pish), a 15th-century prince from the dark, forested mountains of Eastern Europe was his inspiration.

CBS Photo Archive via Getty Images
The popular conception of Dracula runs the gamut from horrific vampire to comic relief (like Grandpa on the TV show "The Munsters"). But what was the real Dracula like?

Accounts of Vlad Tepes' cruelty have been distorted throughout history, and Stoker's adaption seemed to help perpetrate these distortions. The prince was bestowed with the surname "Tepes" ("Impaler") based on his fondness for impaling victims. It was his father from whom he proudly took the name "Dracula" ("Son of the Dragon"). Tepes was no vampire, although one historic account details how he drank a victim's blood [source: West Grey Times]. And Tepes certainly wasn't immortal (it's unclear how he died), as Stoker's count is.

But Stoker wasn't just inspired by the prince's name. Tepes' reign was a cruel and bloody one.

When investigating sensational history, it's easy to find grossly exaggerated tales that obscure the facts. In the rare case of Vlad Tepes, little exaggeration is needed. Tens of thousands of people were tortured, maimed or died by his hand or command [source: University of Louisiana]. This isn't in dispute -- it's accounts of Tepes' motives where distortion tends to emerge.

As the prince of Wallachia, a region in Romania, and a defender of Christianity against the Muslim Turks, Tepes made many powerful enemies. His enemies spread propaganda about the ruler, which inadvertently assured Tepes' place in history. Tepes' deeds and atrocities made such an impression, in fact, that an unflattering epic poem about him was published on the Gutenberg printing press just eight years after the same moveable type was used to print the first Bible [source: Mundorf and Mundorf]. Had his detractors not campaigned against him, generating publications that survive today, Tepes' legacy may have been lost.

So who was this man? Was Tepes as bloodthirsty in real life as his fictional counterpart is in movies and books? The short answer is yes -- even more so. Read about the real Dracula on the next page.

Vlad the Impaler

Bram Stoker's fictionalization of Vlad Tepes spurred scholarly research into the real man. Research has attempted to show the motives for his murderousness. Tepes desired a unified Romania -- free from the outside influences of Germany, Hungary and the Turks.

His consolidation of local power was harsh. On Easter Day, 1456, Tepes invited regional nobility to dine with him. Following the meal, he had the old and infirm murdered and marched the remaining guests 50 miles to a dilapidated castle, which he took as his own. There, he put the nobility to hard labor restoring it. Most died during from maltreatment and exhaustion; those who didn't were impaled alive on spikes outside the castle when restorations were complete [source: Carroll].

Imagino/Getty Images
A painting of Vlad (Dracula) Tepes, the 15th-century prince who inspired Bram Stoker's fictional vampire

Vlad's father, Vlad Dracul, ruled Wallachia from 1436 to 1442, was unseated by his countrymen and regained the throne from 1443 to 1446. Vlad Tepes served in the same position from 1456 to 1462 [source: Tacitus]. When he was inducted into the Order of the Dragon, a secretive organization of Christian knights, he took the name "Dracula." The name would be replaced by the nickname "Tepes" from those who feared and hated him.

Vlad Dracula's social ideologies were contradictory. He wanted to be remembered as a saint -- he murdered a Catholic monk who denied that Tepes would be canonized (sainted) [source: Carroll]. Yet his behavior was hardly saintly. Having come to view destitution as a scourge on his domain, Tepes invited his poverty-stricken subjects to dine with him. At the end of the dinner, he had the dining room locked, and his guards set fire to it, killing those inside [source: Marinari].

His foreign enemies suffered equal (if not worse) fates than his subjects. For four years, Tepes and his younger brother were imprisoned by Turks after their father sent them as tribute to the sultan Mehmet. Tepes' father had become a puppet leader of Wallachia for the Turks, and his sons were imprisoned to guarantee their father's continued loyalty [source: Fasulo]. Tepes was meant to become a future puppet leader like his father. But rather than keep allegiance to the Turks, he resolved to fight them.

When he became prince in 1456, Tepes took strides toward Romanian independence. He developed biological warfare, sending subjects disguised as Turks, stricken with infectious disease, to live among the armies in their camps [source: Marinari]. For those Turks who survived, when they invaded the capital of Wallachia, Tirgoviste, they found a forest (about one-half mile by two miles in dimension) made entirely of corpses of captured prisoners impaled on spikes. The invaders left quickly [source: Carroll].

Impalement, the method of execution that gave Tepes his name, is an extraordinarily painful way to die. Tepes ensured maximum pain when he impaled his victims by rounding the ends of spikes and oiling them to reduce tearing. Spikes were introduced into the victim's anus and pushed in until the other end emerged from the victim's mouth. The impaled victim was then hoisted vertically, and left to writhe in agony, sometimes for days [source: Fasulo].

The aged vampire in Stoker's novel required blood to stay alive; Tepes shed blood by the bucketful to promote his lifelong goals. Conservative estimates put his victim count at 40,000 [source: University of Louisiana]. It's also significant to note that eating and death were so intertwined in Tepes' life. He often dined with guests before killing them, and he was reputed to have taken meals outdoors, among impaled dead and dying [source: Martin]

Why is blood such a significant symbol of vitality and power in fiction, allegory and reality? Find out about the symbolism of blood on the next page.

Blood: Symbol of Life

Most Christians wouldn't infer vampirism from the story of the Last Supper. Christ offers the chalice containing wine to signify his blood to his disciples and directs them to drink it. But there is a parallel between the Eucharist and vampire legends: Both suggest that the consumption of blood is an act of obtaining vitality.

Christ told his disciples he'd shed his blood for their forgiveness. By drinking it, they were taking part in his everlasting divinity. Similarly, through ingesting the blood of others, vampires of lore may live eternally here on Earth.

According to some sources, blood is also reputed for its mythic ability to maintain beauty. When Bram Stoker's fictional Dracula fed on blood, his appearance reverted to a handsome, youthful version of himself. The 16th-century Hungarian countess Elizabeth Bathory is said to have used the blood of her murdered victims to promote her skin's health. Some Renaissance-era women believed applying the blood of doves to their skin could maintain beauty [source: McNally]. And even today, some women apply rouge or pinch their cheeks to create the appearance of a healthy flush.

Anthropophagy (cannibalism) is another example of the symbolic (and literal) vitality derived from eating the flesh or drinking the blood of others. Through cannibalism, symbolic vitality generally comes from two sources: kin and the vanquished. Endocannibalism refers to eating the flesh of a member of one's group. In some cultures, eating the flesh of a relative serves as a way of carrying on the line of ancestors [source: Goldman]. Exocannibalism is eating the flesh of one outside the eater's group, like a conquered foe. Tepes committed exocannibalism in one account when he ingested the blood of captured Turks, although there's no evidence he believed he gained any tangible power from the act. Rather, he ate blood-dipped bread from a bowl as a signal of what the future held in store for the Turks [source: West Grey Times].

Uwe Zucchi/AFP/Getty Images
Cannibalism is associated with madness in the modern, developed world. German Armin Meiwes was convicted of manslaughter for killing and eating another, willing human.

Instances of nonritual cannibalism also produce vitality. Perhaps the most famous case of cannibalism took place in 1972, when an airplane carrying the Uruguayan national soccer team crashed in the Andes Mountains. Several members were left alive and resorted to cannibalizing their dead teammates to survive for more than two months [source: Walton].

It appears our ancestors took some time to develop mores -- cultural restrictions -- against cannibalism. Evidence of anthropophagy as recent as around A.D. 1100 has been uncovered at Anasazi settlements in the Southwestern United States [source: Melmer]. And genetic researchers have found a gene variant spread among humans throughout the world that suggests we descended from cannibals [source: BBC].

Vampire legends, then, may be allegories for real-life monsters -- perhaps like Vlad Tepes -- that have refused to honor the sacred taboo against consuming the vitality of other humans

relationships need to move forward, but we can't [Art]

relationships need to move forward, but we can't

relationships need to move forward, but we can't

Howstuffworks "How Robotic Vacuums Work" [Robots][Technology]

How Robotic Vacuums Work

by Julia Layton

Introduction to How Robotic Vacuums Work

Photo courtesy iRobot Roomba Red. See more robotic vacuum images.

There are those of us who clean once a week, and there are those of us who clean when the in-laws come to visit. The appeal of the robotic vacuum reaches both camps: Either way, the house is a bit more spotless with minimal human input.

Today's robotic vacuums are a far cry from the first models that you had to track down, stranded somewhere in your house, by their melancholy, "I'm out of power" beeping. The latest products clean your house, remember the layout to increase efficiency, dump their own dirt in a receptacle and find their way back to the charging station so they can rejuice.

In this article, we'll learn about robotic vacuuming, do an in-depth examination of the iRobot Roomba Red and check out some of the other vacuuming robots on the market.

Roomba Videos Check out Roomba in action! Watch this robotic vacuum clean, avoid stairs and charge itself in three videos provided by iRobot. Roomba Cleaning Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth Roomba Self-charging Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth Roomba Avoiding Stairs Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth

Robotic Vacuum Basics
There are a lot of models of robotic vacuums available today, and they range in price from $50 all the way up to $1,800. These vacuuming robots are typically low-slung and compact, meaning they can get under furniture that a regular upright vacuum cleaner can't.

Courtesy HowStuffWorks Shopper Clockwise from top left: iRobot Roomba 4210; iRobot Roomba Red; Electrolux Tribolite; Lentek Intelli-Vac

Most manufacturers will tell you that a robotic vacuum is meant to supplement a standard, human-pushed vacuum cleaner, not replace it. They're meant to perform daily or weekly touch-ups to keep your home cleaner in between regular vacuuming cycles. Still, if you're someone who never vacuums in the first place, a little robotic helper can certainly get your floor cleaner than it is right now, and you hardly have to lift a finger.

By far the most popular robotic vacuum in the United States is iRobot's Roomba, which comes in various models ranging from the base-model Roomba Red to the super high-tech Roomba Scheduler. HowStuffWorks has a Roomba Red ($150 MSRP) that we're going to try out and dissect for this article. Let's start by checking out what's under the hood.

Inside a Roomba

The Roomba Red is approximately 13 inches (33 cm) in diameter and 3.5 inches (9 cm) tall. An external examination reveals the following parts:

Roombas run on a rechargeable NiMH battery. The Roomba Red battery pack is rated at 3 amp-hours and takes about seven hours to fully charge to about 18 volts. Some of the more recent Roomba models have cut that charge time down to about three hours. A full charge equals approximately two hours of cleaning time, which in the Roomba world means vacuuming three medium-size rooms before it needs to rejuice. The mobility system consists primarily of two motor-driven, tracked wheels. Roomba steers by alternating the power supplied to each wheel.

Roomba has a total of five motors:

• One driving each wheel (2 total)
• One driving the vacuum
• One driving the spinning side brush
• One driving the agitator assembly

In the following sections, we'll address each of the systems that make Roomba work, beginning with the most robotically interesting one: the navigation system.

Smart Carpet German companies Vorwerk and Infineon have teamed up to produce a prototype carpet that works in tandem with a robotic vacuum. The underside of the carpet is embedded with RFID tags, and the vacuum is equipped with an RFID reader and a digital map of the carpet's RFID locations. The tags direct the vacuum around the room for complete coverage and can tell it to reclean a specific area if it didn't spend enough time there. See Discovery Channel: Intelligent Carpet Directs Robot Vacuum to learn more.

Roomba Navigation

The self-navigation system is what makes a robotic vacuum robotic, and the biggest difference between a $50 model and a $1,500 model is the precision of the navigation sensors. Roomba uses iRobot's AWARE(tm) Robotic Intelligence System to make many decisions for itself, so minimal human input is required. The AWARE system is made up of multiple sensors that pick up environmental data, send it to robot's the microprocessor and alter Roomba's actions accordingly.

Roomba Red's microprocessor

According to iRobot, the system can adapt to new input up to 67 times per second.

We'll look at the following parts to learn how Roomba navigates its environment:

Pressing on the bumper activates the object sensors (below).

The first thing Roomba does when you press "Clean" is calculate the room size. iRobot is a bit hazy on how it does this, but HowStuffWorks believes that it sends out an infrared signal and checks how long it takes to bounce back to the infrared receiver located on its bumper. Once it establishes the size of the room, it knows how long it should spend cleaning it.

While Roomba is cleaning, it avoids steps (or any other kind of drop-off) using four infrared sensors on the front underside of the unit. These cliff sensors constantly send out infrared signals, and Roomba expects them to immediately bounce back. If it's approaching a cliff, the signals all of a sudden get lost. This is how Roomba knows to head the other way. When Roomba knocks into something, its bumper retracts, activating mechanical object sensors that tell Roomba it has encountered an obstacle. It then performs (and repeats) the sequential actions of backing up, rotating and moving forward until it finds a clear path.

Another infrared sensor, which we'll call a wall sensor, is located on the right side of the bumper and lets Roomba follow very closely along walls and around objects (like furniture) without touching them. This means it can clean pretty close up to these obstacles without bumping into them. It also determines its own cleaning path using what iRobot says is a pre-set algorithm that achieves complete floor coverage.

Roomba Red's "cleaning algorithm"

When HowStuffWorks tried it out, we found that Roomba starts cleaning in an outward-moving spiral and then heads for the perimeter of the room. Once it hits an obstacle, it believes it has reached the perimeter of the room. It then cleans along the "perimeter" until it hits another obstacle, at which point it cleans around it, finds a clear path and proceeds to traverse the room between objects like walls and furniture until the allotted cleaning time is up. The idea appears to be that if it cleans for a certain amount of time, it'll cover the whole floor, but whether it actually achieves complete floor coverage is pretty much hit or miss.

Roomba can clean for about two hours on a single charge. If you have the self-charger, Roomba will return and connect to the charger all by itself when the battery power is low (the self-charger is sold as an add-on to the Roomba base model but comes included on most of the higher Discovery models). It accomplishes this using the infrared receiver on its front bumper. When the battery power gets low, the vacuum starts looking for the infrared signal emitted by the charger. Once it finds it, Roomba follows the signal and docks itself to the charger. Some robotic vacuums with this self-charging feature will head back out to resume cleaning once they're fully recharged.

So the Roomba is smart enough to clean your floors while you're at the movies, but there are still some decisions you need to make for it. First, you need to remove small obstacles from the floor so Roomba doesn't get stuck on them or try to suck them up. You also need to tell Roomba where it should not go. Using included virtual wall units, you can keep the robot within certain boundaries. Virtual walls send out infrared signals that Roomba picks up with the receiver on its bumper. When it picks up a signal from a virtual wall, it knows to turn around and head the other way.

Roomba's sensors allow it navigate your home with relative autonomy. Now let's find out how it accomplishes its real purpose: vacuuming.

Roomba Cleaning

According to iRobot, more than half of Roomba owners name their little vacuuming buddy. Electrolux, the maker of the high-end Tribolite robotic vacuum, reports that it receives letters and pictures from families that own its product. Still, most people don't buy a robotic vacuum because they're looking for a low-maintenance pet. They buy it because their floors get dirty.

Roomba Red has a three-part cleaning system:

If you remove the agitator assembly, you can see two dirt sensors:

• The spinning side brush sticks out past the Roomba shell to reach spots the underside can't access. It spins along walls to kick up dirt and direct it into the vacuum area. The brush on the opposite side of the Roomba directs any wayward dirt back under the unit to be sucked up.
• The agitator on the underside of the Roomba consists of two counter-rotating brushes that grab dirt and other debris and deposit it directly in the dirt bin.
• The vacuum sucks up dirt and dust as Roomba moves along the floor.

You typically need to empty the dirt bin at least once for each room the Roomba vacuums, and possibly two or three times depending on how dirty your floors are. Roomba doesn't know when the bin is full -- it just keeps going. There's a filter you'll need to replace when it gets too clogged, but there's no vacuum bag -- you just dump the bin and put it back in the unit.

As far as cleaning power goes, the iRobot Web site states that Roomba has "as much suction as a standard upright," although it offers no specifications. When HowStuffWorks tried out the Roomba Red, we found that it cleans quite well on hardwoods and linoleum, and it picks up a good amount of the dirt and pet hair on low- and medium-pile carpet. According to iRobot, Roomba is not intended for deep-pile carpet.

Now, when you're pushing a vacuum through your home, you make decisions. If you see that an area is especially dirty, you spend more time there. When you pass from the linoleum of the kitchen to the carpet in the dining room, you turn a knob on the vacuum so it can achieve its optimum efficiency on the type of floor its cleaning. As a robot, Roomba should be able to at least partially replicate a human's ability to clean effectively.

In order to figure out which areas need extra cleaning, Roomba Red has two dirt sensors located immediately above the agitator brush. These dirt sensors are acoustic impact sensors. When the agitator kicks up a large amount of dirt, the dirt causes more vibration when it hits the metal plates of the sensors. The sensors detect that increase and tell Roomba to go over the area again. To make the transition between floor types, Roomba's cleaning deck (which houses the agitator setup) automatically adjusts its height when it senses a half-inch (1.3-cm) rise in the floor surface.

One thing Roomba can do that a human and an upright vacuum can't is get completely under furniture. Because Roomba Red is only about 3.5 inches (9 cm) tall, it can easily get under most coffee tables, night stands, beds and some couches. The ability to clean under furniture is arguably one of the biggest draws of the robotic vacuum.

The Roomba Red is a handy device, but it's only one example of a vacuuming robot. In the next section, we'll check out some of the other robotic vacuums available today.

Roomba Videos Check out Roomba in action! Watch this robotic vacuum clean, avoid stairs and charge itself in three videos provided by iRobot. Roomba Cleaning Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth Roomba Self-charging Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth Roomba Avoiding Stairs Windows Media Player: High bandwidth Medium bandwidth Low bandwidth Real Media Player: High bandwidth Medium bandwidth Low bandwidth

Robotic Vacuum Models

There are lots of vacuuming robots on the market, and all of them cover certain tasks -- most notably, they vacuum. Most models also feature some sort of obstacle-avoidance system and come equipped with a remote control. Beyond that, there are differences between products that account for the great range in price. Here, we'll discuss several robotic vacuums and their distinguishing characteristics.

Photo courtesy Amazon.com Lentek RV01 IntelliVac Priced at $70, the RV01 is probably most notable for its affordability. It features a sweeper attachment for hardwoods and has four built-in cleaning patterns (random, spiral, perimeter and "z") that it uses for each room. Lentek claims this ensures complete floor coverage. This model is only meant for hardwoods and low-pile carpet.

Photo courtesy HowStuffWorks Shopper iRobot Discovery 4210 More expensive and more helpful than the Roomba Red ($150 MSRP), the 4210 model costs about $280 and comes standard with the self-charging base station that calls the robot home. It takes less than three hours to charge, has a larger dust bin than previous models and will clean a single area for as long as you want it to.

Photo courtesy Amazon.com iRobot Roomba Scheduler At $320, the Scheduler is iRobot's current top-end robotic vacuum, although everything that makes the Scheduler the Scheduler is available for purchase as add-ons for some of the other Roomba models. This model lets you set cleaning cycles in advance. You can tell it to clean for 40 minutes every Tuesday and 80 minutes every Saturday and adjust the schedule at will using the remote control.

Photo courtesy HowStuffWorks Shopper Kärcher RC3000 The RC3000 costs about $1,500 and features some pretty cool capabilities. For one thing, not only does it find its way back to the charging station, but it also empties its own dust bin while it's there. It only takes about 15 minutes to fully charge, and a full charge gets you about 60 minutes of continuous cleaning. Once it recharges, it heads back out again to pick up its cleaning where it left off. The RC3000 also has a quiet mode.

Photo courtesy HowStuffWorks Shopper Electrolux Trilobite EL520A At $1,800, the Tribolite is at the top end of the robotic cleaning spectrum. It uses sonar to navigate and can easily avoid almost any type of obstacle. You can program it to clean at specific times and choose between three cleaning modes. The Tribolite creates a map of the room it's cleaning and calculates a cleaning path that will maximize coverage. It recognizes doorways by way of little magnetic strips that you apply, and it uses them to keep itself in the room you want it to clean. When it runs out of power, it returns itself to the charging station and resumes cleaning once it's rejuiced.

As you can see from the pricier models, the trend in robotic vacuums is toward a more complete home robot that will do more than just clean your floor. Products sold as vacuuming robots are starting to offer additional features like Internet connectivity, home surveillance and air-purification. The future is likely to see home robots that download music, answer your phone and preheat your oven while they vacuum your house.

For more information on robotic vacuums and related topics, check out the links on the next page.

Hydroelectric power rocks my socks! - [Art]

Hydroelectric power rocks my socks!

Hydroelectric power rocks my socks!

Howstuffworks "How Laser Weapons Work" [Interesting]

Howstuffworks "How Laser Weapons Work"

How Laser Weapons Work

by Craig Freudenrich, Ph.D.

Introduction to How Laser Weapons Work

Lambert/Hulton Archive/Getty Images
Could this young man use
his laser gun to stun
an opponent? See more
laser pictures.

You may have seen them in "Star Wars," "Star Trek," and other science fiction films and shows. The X-wing fighters, the Death Star, the Millennium Falcon and the Enterprise used laser weapons in great fictional battles to conquer and/or defend the universe. And starships aren't the only ones packing laser heat. Han Solo and others carried the blaster in "Star Wars." And Captain Kirk and other Starfleet personnel used phasers in "Star Trek." All of these weapons used directed energy, in the form of a laser beam, to disable or kill an opponent.

But what are the advantages of using a laser as a weapon? Is it even possible? Could you use such a weapon to stun an opponent? These questions are being addressed by the Air Force Research Laboratory's Directed Energy Directorate. This program is developing high-energy lasers, microwave technologies and other futuristic weapons systems, such as the Airborne Laser and the PHaSR.

Lasers and other directed-energy weapons have many advantages over conventional projectile weapons like bullets and missiles:

• The weapons' light outputs can travel at the velocity of light.
• The weapons can be precisely targeted.
• Their energy output can be controlled -- high-power for lethal outcomes or cutting and low-power for nonlethal outcomes.

The Air Force has already developed three weapons systems that are being tested and, in some cases, used. These systems include the Airborne Laser (Advanced Tactical Laser), the PHaSR and the Active Denial System. Read on to find out how lasers and these weapons systems work.

Video Gallery: Lasers The anthrax scares in New York and Florida a few years ago underscored the need for rapid detection of biological weapons. Scientists have developed a new laser technique that could detect anthrax in real time. See how anthrax lasers and biohazard technology work in this video from ScienCentral. Researchers at Intel and the University of California, Santa Barbara demonstrated the world's first electrically driven hybrid silicon laser, addressing one of the last hurdles to producing low-cost, highly integrated silicon photonic chips for use inside and around PCs, servers and data centers.

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How can a laser be a weapon?

At its most basic, a laser is a light source. To understand how it can become a weapon, it's helpful to think about how it's different from the light sources that are around you every day. Start with an ordinary incandescent light bulb. The bulb sends light waves out in every direction. These waves, just like waves in water, have peaks and troughs, or high points and low points. If you were able to see each light wave coming from an incandescent bulb, you'd see lots of peaks and troughs passing you at the same time. There are also lots of frequencies, or colors, of light coming from a light bulb, and they all combine to create what looks like white light.

Dick Luria/Photodisc/Getty Images
This industrial cutter uses lasers to get the job done.

Now, think of a flashlight. A flashlight's beam is more focused than what comes from a naked light bulb. Most of its light travels in one direction, depending on where you point the flashlight. There are still lots of frequencies of light that combine to create white light, and the peaks and troughs of the different light waves pass by at different times.

A laser is even more focused than a flashlight. It creates only one wavelength, or color, of light. The peaks and troughs from the light waves are also synchronized peak to peak and trough to trough. This means that the different waves don't interfere with each other. This light travels only in one direction. The light beam can be tightly focused and remain so over great distances. Lasers can produce light of tremendous powers (1,000 to 1 million times stronger than a typical light bulb). Various types of lasers can produce various wavelengths of light, from the infrared range through the visible wavelengths to the ultraviolet range.

Light is basically moving energy. A laser produces very intense energy that can travel over very long distances. That's why a laser can become a weapon while the light from an incandescent bulb typically can't.

To do this, a laser has to produce light in a nonconventional way. "Laser" stands for light amplification by stimulated emission of radiation. In other words, a laser produces light by stimulating the release of photons, or light particles. A laser needs four basic parts to do this:

• Lasing medium: a source of atoms that get excited and emit light of a specific wavelength. The medium can be a gas, liquid or solid.
• Energy source: primes or pumps the atoms in the lasing medium to an excited state
• Mirrors: a full mirror and a half-silvered mirror. The mirrors allow the emitted light to bounce back and forth within the lasing medium cavity and ultimately to escape to the outside
• Lens: most lasers have some type of lens to focus the beam.

The lasing process is all about storing and releasing energy. An energy source injects energy into the lasing medium. The energy excites electrons, which move up to higher energy levels. When the electrons relax, they emit photons. The photons move back and forth between the mirrors, exciting other electrons as they go. This produces powerful, focused light.

Next, we'll start to look at some of the lasers being used for the military.

Military Lasers

There are many different types of lasers:

• Solid state lasers have a lasing medium that is solid crystal, like the ruby laser or the neodinium YAG laser, which emits 1.06 micrometer wavelength.
• Gas lasers have a lasing medium that is a gas or combination of gases, such as helium-neon laser or carbon dioxide laser, which emits 10.6 micrometer wavelengths (infrared).
• Excimer lasers have a lasing medium that is a combination of reactive gases, like chlorine or fluorine, and inert gases, like argon or krypton. The argon fluoride laser emits ultraviolet light of 193 nanometer wavelengths.
• Dye lasers have a lasing medium that is a fluorescent dye, such as rhodamine. They can be tuned to a variety of wavelengths within a certain range. The rhodamine 6G dye laser can be tuned from 570- to 650-nanometer wavelengths.
• Carbon dioxide lasers are being explored by the military because they're powerful infrared lasers that can be used for cutting metal.

Image courtesy Flavio Robles/Creative Services Office, Lawrence Berkeley National Lab
Illustration of a free electron laser. A beam of electrons is sent through an undulator -- an array of magnets with alternating north and south poles. The magnetic field in the undulator forces each bunch of electrons to oscillate back and forth, causing them to emit a laserlike beam of light.

There are several lasers currently being used for military purposes. One that's being researched and developed is the free electron laser (FEL). In the 1970s, Stanford physicist John Madey invented and patented the FEL, which consists of an electron injector, a particle accelerator and a magnetic undulator or wiggler. It works like this:

1. The electron injector injects a pulse of free electrons into the particle accelerator.
2. The particle accelerator accelerates the electrons to near the speed of light (300,000 km/s)
3. The electrons move through the undulator or wiggler, which is a series of magnets with alternating north-south directions.
4. Inside the wiggler, the electrons oscillate back and forth. With each bend, they emit light of a specific wavelength.
5. The spacing of the magnets within the wiggler controls the wavelength of emitted light. So, the FEL laser can be tuned by changing the magnet spacing.
6. In theory, the FEL can be tuned from the infrared region to the X-ray region of the electromagnetic spectrum.

FELs have been used to produce high-energy infrared light and synchrotron X-rays for research purposes. The FEL was also a laser of interest for the Defense Department's Strategic Defense Initiative (President Reagan's "Star Wars" program). Recently, the U.S. Naval Postgraduate School acquired Madey's original FEL developed at Stanford University, to use for military research.

In 1977, the U.S. Air Force developed a chemical oxygen-iodine laser (COIL). The energy source for the COIL is a chemical reaction, and the lasing medium is molecular iodine. Here's how it works: atoms, heat and byproducts, including water vapor and potassium chloride.

1. A chemical reaction occurs between chlorine gas and liquid mixture of hydrogen peroxide and potassium hydroxide.
2. The chemical reaction produces single oxygen
3. Molecular iodine gets injected into the laser. The singlet oxygen provides the energy to get the iodine atoms to lase and emit infrared light at a wavelength of 1.3 micrometers.
4. The laser can emit light continuously or the light can be pulsed, which increases the efficiency of the laser.

The COIL laser is used aboard the Air Force's Airborne Laser, which we'll talk about next.

The Airborne Laser

Photo courtesy Kirtland AFB/
U.S. Air Force
Air Force's Airborne Laser
is an aircraft equipped
with a chemical laser. It's designed to shoot down missiles in early flight.

In the Gulf War, Saddam Hussein's forces fired SCUD missiles at Israel and U.S. bases in the Middle East. The Patriot missile defense system was deployed to protect American interests. Patriot missiles can destroy incoming missiles on their downward path, but what if you could catch it earlier and destroy the missile during its boost phase (the upward path near its origin)? That's what the U.S. Air Force's Airborne Laser (ABL) is designed to do -- it's being developed by Boeing, Northrup Grumman and Lockheed Martin contractors.

The ABL is mounted in a modified Boeing 747 jumbo jet. It consists of four lasers, advanced adaptive optics, sensors, and computers to locate, track and destroy missiles. It works like this:

1. Infrared sensors detect the heat signature of a boosting missile and report information to an Active Tracking Laser.
2. The Active Tracking Laser tracks the missile and reports relevant tracking information (distance, speed, altitude).
3. The Tracker Illuminator Laser scans the target and figures out where best to aim the high-energy laser.
4. The Beacon Illuminator Laser shines on the target, determines the amount of atmospheric turbulence between the ABL and the target, and relays this information to the adaptive optics system in the aiming mechanism of the high-energy laser.
5. The Adaptive Optics system is made of deformable mirrors that compensate for atmospheric turbulence. The turret mounted in the nose houses a 1.5-meter telescope as part of the optics system.
6. The COIL laser fires a megawatt beam at the target. The beam exits the ABL through the nose-mounted turret.
7. The high-energy laser beam penetrates the skin of the target missile and disables or explodes it, depending upon where the beam strikes.

All of the operations are coordinated by computer.

The Air Force is currently testing the ABL and says that its range is in the order of hundreds of kilometers. The ABL will require a crew of six when it is fully operational, and they'll wear special safety goggles to protect their eyes from possible reflections of the beams by water droplets in the air.

High-energy lasers like those developed for the ABL are being designed and developed for use on land and at sea. These lasers would be truck- or ship-mounted and capable of shooting down incoming missiles, artillery shells and possibly enemy aircraft.

Nonlethal and Personal Laser Weapons

Photo courtesy U.S. Department
of Defense
The Active Denial System directs millimeter radio frequencies at a target and causes an intense burning sensation.

Now we know that high-energy lasers are used to shoot down missiles, but do they have nonlethal uses, too? Yes. In fact, one such system has been tested and will soon be operational. It's called the Active Denial System (ADS). The ADS isn't a laser, but a truck-mounted high-energy radio frequency generator and directional antenna. A generator inside creates a 95 GHz millimeter wave. (Millimeter waves have wavelengths of 1 to 10 millimeters and frequencies of 30 to 300 GHz.) The directional antenna focuses the millimeter waves and allows the operator to point the beam. The millimeter beam penetrates the skin of anyone in its path to a depth of 1/64th of an inch, about the thickness of three sheets of paper. Like a microwave oven, the energy of the beam heats water molecules in the skin tissue and causes an intense burning sensation. The beam doesn't permanently injure because it doesn't penetrate very far, and when a person moves out of the beam, the sensation goes away (see How Military Pain Beams Will Work).

Suppose you could momentarily stun or distract an opponent. The Air Force has developed a device that will do just that -- the Personnel Halting and Stimulation Response (PHaSR). The PHaSR incorporates two low-power diode lasers, one visible and one infrared. It's about the size of a rifle and can be fired by an individual. The laser light temporarily distracts or "dazzles" the target person without blinding him.

The Department of Defense is also developing other optical distracter devices that could temporarily impair a target's vision.

You don't have to be a sci-fi fan to be wondering if there are any personal laser weapons on the market for civilians. Maybe something like those you see in science fiction shows? Can an average person purchase or build one? A company called Information Unlimited advertises a laser ray gun. After signing a hazardous equipment affidavit and purchasing the plans, you can purchase the hardware and assemble your very own laser gun.

Photo courtesy Kirtland AFB/U.S. Air Force
The Personnel Halting and Stimulation Response (PHaSR) is a rifle-size laser weapon system that uses two nonlethal laser wavelengths to deter an adversary.

Information Unlimited's laser ray gun is a solid state laser that uses a flash lamp as an energy primer and a neodinium glass rod as the lasing medium. It works much like the ruby laser described in How Lasers Work. It requires 12 volts of DC power, which comes from AA batteries. It emits infrared light of 1.06 micrometer wavelength in short 3 joule pulses for a total of 500 joules of energy. The beam is focused with a collimating lens, which straightens the beams and makes them parallel. It's classified as a hazardous class IV laser, and the company claims that it's capable of burning holes in most materials (infrared lasers can do these things). So you might not want to pick one up for your 9-year-old's birthday.

To learn more about laser weapons, take a look at the links on the next page.

State Blames Missing Primary Votes on Clerical Error [Politics]

I call shenanigans
~P

State Blames Missing Primary Votes on Clerical Error|abc27 News

State Blames Missing Primary Votes on Clerical Error

   posted 7:57 am Tue April 29, 2008 - Harrisburg, Pa. (AP)

Pennsylvania election officials have revised their unofficial vote count for the presidential primary.

They've determined that a clerical error had kept about 26,000 Northampton County votes out of the state tally.

Department of State spokeswoman Leslie Amoros says the problem was traced to a mistaken assumption that all of the county's votes had been recorded.

After the numbers were corrected Monday, about 21,000 votes were added to the Democratic presidential race and about 5,300 to the Republican presidential race.

Sen. Hillary Clinton picked up 13,287 votes and Sen. Barack Obama (web|news|bio) picked up 7,678 votes for the Democratic presidential nomination.

Clinton's lead of 31,583 to 19,893 in Northampton County now matches The Associated Press figures.

(Copyright 2008 by The Associated Press. All Rights Reserved.)