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Sunday, March 31, 2013
In Atlanta test-cheating scandal, a case for 'good apples'
Indictments of 35 Atlanta educators in a test-cheating scandal may be shocking. But preventing such scandals requires a refocus on tapping the conscience of public servants to choose honesty.
In this 2011 photo, outgoing school superintendent Dr. Beverly Hall, center, arrives for her last school board meeting at the Atlanta Public Schools headquarters. Hall and nearly three dozen other administrators, teachers, principals and other educators were indicted March 29, 2013, in one of the nation's largest cheating scandals.
Atlanta Journal-Constitution/AP Photo
EnlargeA jury in Georgia indicted 35 Atlanta educators on Friday in what has been called the largest test-cheating scandal in American public schools.
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Those charged ?conspired to either cheat, conceal cheating, or retaliate against whistle-blowers? in order to boost the test scores of students ? but with the aim to benefit themselves, prosecutors said.
The indictments come two years after state investigators revealed that 178 administrators and staffers ? including 38 principals ? were involved in a scandal spread across dozens of schools in Atlanta from at least 2005 to 2010. The charges even include a former superintendent, Beverly Hall, who had been designated National Superintendent of the Year in 2009.
While the scope and seriousness of the test cheating is shocking, the indictment helps reinforce the fact that plenty of school personnel in Atlanta were willing to be whistle-blowers or informants. They either stood up to pressure from superiors and took a stand for honesty, or eventually came clean about their own complicity.
?I wanted to clear my conscience,? Jackie Parks, a former third-grade teacher at Venetian Hills Elementary School, told The New York Times. She d agreed to wear a wire-tap for investigators in order to record fellow teachers as they secretly erased wrong answers on state-required tests and marked them as correct.
Many school districts in the United States have recently discovered teachers or principals altering test scores to create a better impression of their schools or to earn more money. This has forced changes in testing procedures and even cast doubt on the wisdom of high-stakes testing as a tool of holding public education more accountable for what students actually learn.
Yet no matter what the pressure on schools to perform, there is no excuse for cheating.
Schools should certainly run a ?tight ship? against unethical behavior and be aware of pressures on educators. Most of all, however, they must encourage honesty and trust in teachers and administrators.
It can be difficult to screen for ?bad apples? while also reinforcing ?good apples.? Yet trust is a two-way street, and many organizations find that being more trustful of employees helps them to be trustworthy.
Studies of dishonesty by behavioral economist Dan Ariely find that a fear of getting caught does little to prevent deception. Instead, simply reminding workers of their moral obligations or the consequences of their acts can increase the level of honesty. It is not that people are amoral like blank slates and must be manipulated to be bad or good. Rather with small reminders, they choose good.
Schools are already loaded with ?good apples.? In a 2005 study of Chicago elementary schools, only 3 to 6 percent of classrooms had signs of teachers or administrators altering student exams. The study also found that teachers or schools can make extraordinary gains in test scores without any indication of cheating.
As Harvard University management expert Mark Moore writes: a ?trusting model embodying a more direct appeal to moral principles might actually do a better job of evoking high-minded motives for action and of suppressing low-minded ones.?
Those in public service, such as teachers, and especially those who work with children, should be the most inclined to be honest. This is what makes the Atlanta scandal so startling. The city?s schools have already made reforms with a focus on honesty in testing and a better workplace ethos of sharing a common mission.
Tapping into a person?s conscience is far better than trying to trap a person?s deceit.
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Longtime Massage Therapist Opens Carrollwood Wellness Spa ...
After working as a massage therapist for 12 years, Donna Confalone knew the time was right for her to open her own business. And, for Confalone, the Carrollwood area was the perfect location for her new wellness spa. "I chose Carrollwood to plant my ?
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Source: http://www.16g.org/longtime-massage-therapist-opens-carrollwood-wellness-spa/
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Mathematician publishes 2013 Major League Baseball projections
Mar. 28, 2013 ? It looks like 2013 will be a thrilling season for baseball fans as four of the six divisions can be expected to deliver tight races, says baseball guru NJIT Associate Professor and Associate Dean Bruce Bukiet. Over the years, Bukiet has applied mathematical analysis to compute the number of regular season games each Major League Baseball team should win. Though his expertise is in mathematical modeling, his projections have compared well with those of so-called experts.
The numbers indicate that only one game might separate the first and second place teams in both the National League's (NL) East and West divisions, with the Atlanta Braves (94 wins) edging out the Washington Nationals (93 wins) in the East and the Los Angeles Dodgers (88 wins) coming in just ahead of the San Francisco Giants (87 wins) in the West. Even in the NL Central, the St. Louis Cardinals (90 wins) don't have much breathing room, winning that division by a projected 3 games over the Cincinnati Reds (87 wins). The Braves, Nationals, Cards, Reds and Dodgers should make the playoffs, while the Giants miss by a single game.
It is hard to believe that in the American League (AL), the contests could be even closer. While the Detroit Tigers should have the best record in baseball (102 wins) and run away with the Central division, with the next best team (the Chicago White Sox) more than 20 wins behind, the other two divisions could end up in ties. In the AL West, Bukiet has the Anaheim Angels and the Oakland Athletics tied with 92 wins each, while in the AL East, he says there could be a 3-way tie!!! The guru predicts that the Toronto Blue Jays, the Tampa Bay Rays and the New York Yankees all will win 87 games. Such results would mean that the Tigers, Angels, and Athletics would make the playoffs, while the other two teams to make the playoffs would be from among the Blue Jays, Rays, Yankees or Texas Rangers, all whom the model show come in at 87 wins.
Bukiet makes these projections to demonstrate and promote the power of math. He wants to show young people that math can be fun, that it can be applied to improve one's understanding of many aspects of life and that if you love mathematics, it can be a great college major and lead to a satisfying career.
Bukiet bases his predictions on a mathematical model he developed in 2000. He has made revisions over the years. His results have led to back-to-back wins for himself in 2010-2011 as predictions champ at baseballphd.net.
Bukiet should have plenty of time this summer to spend doing math since once again his favorite team, the New York Mets, should win the same number of games (74) as they did last year. Once again they should come in fourth in their division, while the Miami Marlins have the worst record in the NL with 59 wins. The worst team overall should be the Houston Astros in their debut in the AL with only 56 successful outcomes and 106 losses. Yes, and once again, for the 21th year in a row, the Pittsburgh Pirates should finish with a losing record.
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The above story is reprinted from materials provided by New Jersey Institute of Technology.
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Source: http://feeds.sciencedaily.com/~r/sciencedaily/living_well/~3/qeqBTqb5-Bs/130329125258.htm
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Singer India.Arie laughs off skin-lightening talk
FILE - In this Jan. 30, 2010 file photo, India.Arie arrives at the annual Pre-GRAMMY Gala presented by The Recording Academy and Clive Davis at The Beverly Hilton Hotel in Beverly, Hills, Calif. The R&B songstress is known for singing about being authentic and celebrating one's true self. But some accused India.Arie of lightening her skin when a publicity photo for her song "Cocoa Butter" released this week made it look as though she were several shades lighter than her dark brown complexion. (AP Photo/Chris Pizzello, File)
FILE - In this Jan. 30, 2010 file photo, India.Arie arrives at the annual Pre-GRAMMY Gala presented by The Recording Academy and Clive Davis at The Beverly Hilton Hotel in Beverly, Hills, Calif. The R&B songstress is known for singing about being authentic and celebrating one's true self. But some accused India.Arie of lightening her skin when a publicity photo for her song "Cocoa Butter" released this week made it look as though she were several shades lighter than her dark brown complexion. (AP Photo/Chris Pizzello, File)
This publicity photo provided by SoulBird/Motown shows the cover artwork for singer India.Arie's single, "Cocoa Butter." The R&B songstress is known for singing about being authentic and celebrating one's true self. But some accused India.Arie of lightening her skin when a publicity photo for her song "Cocoa Butter" released this week made it look as though she were several shades lighter than her dark brown complexion. (AP Photo/SoulBird/Motown, Randee St. Nicholas)
NEW YORK (AP) ? India.Arie is laughing off talk that she may have lightened her skin.
The R&B songstress is known for singing about being authentic and celebrating one's true self. But some accused India.Arie of lightening her skin when a publicity photo for her song "Cocoa Butter" released this week made it look as though she were several shades lighter than her dark brown complexion.
But India.Arie took to Twitter on Friday to deny the accusations, saying she has no desire to bleach her skin because she loves herself and her brown skin "more than ever." She also said that "magnificent lighting" is the cause for her "glow."
She added that she'd like to keep the conversation going, though, on the issue of racism and colorism in the black community.
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Bashir to make first visit to South Sudan since split
KHARTOUM/JUBA (Reuters) - Sudan's President Omar Hassan al-Bashir will visit his long-time foe South Sudan for the first time since its independence next week, an official said on Friday, cementing new deals on oil and border security between the two countries.
The African neighbors agreed this month to resume cross-border oil flows and defuse tensions that have plagued them since South Sudan seceded in July 2011 following an agreement which ended decades of civil war.
Bashir had originally planned to visit Juba a year ago but canceled the trip when border skirmishes between the countries' armies in April brought them close to a full-blown conflict.
He has now accepted an invitation from his southern counterpart Salva Kiir to go to South Sudan's capital Juba next week, Bashir's spokesman Imad Said told Reuters. He gave no date.
The two countries went their separate ways without resolving a long list of disputes over the ownership of disputed territory, the legal status of each others' citizens and how much the landlocked south should pay to transport its oil through Sudan.
Juba shut down its entire oil output of 350,000 barrels a day in January last year at the height of the dispute over pipeline fees - a closure that had a devastating effect on both struggling economies.
Under the new deals, both sides agreed to restart the oil flow, grant their citizens free residency in the other country, boost border trade and encourage close cooperation between their central banks.
They also withdrew their troops from their shared border as agreed in a deal brokered by the African Union in September.
Both sides still need to decide on who owns Abyei and other disputed regions.
Bashir last visited Juba on July 9, 2011 to attend the ceremony marking South Sudan's separation.
Around two million died in the decades-long civil war between Khartoum and Sudan's south, fueled by religion, oil, ethnicity and ideology. It ended in a 2005 peace deal that paved the way for the southern secession.
(Reporting by Khalid Abdelaziz in Khartoum and Moses Misuk in Juba; Writing by Ulf Laessing; Editing by Andrew Heavens)
Source: http://news.yahoo.com/bashir-first-visit-south-sudan-since-split-131525825.html
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Saturday, March 30, 2013
U.S. commandos hand over troubled area to Afghans
KABUL, Afghanistan (AP) ? U.S. special operations forces handed over their base in a strategic district of eastern Afghanistan to local Afghan special forces on Saturday, senior U.S. commanders said. The withdrawal satisfies a demand by Afghan President Hamid Karzai that U.S. forces leave the area after allegations that the Americans' Afghan counterparts committed human rights abuses there on U.S. orders.
The transfer of authority ends a particularly rocky episode in the strained relations between the U.S. and Karzai. He had insisted that U.S. forces leave Nirkh district in Wardak province over the alleged torture, kidnapping and summary execution of militant suspects there ? charges U.S. officials firmly denied.
The incident shows the larger struggle of Karzai's government to assert its authority over security matters, even as its green security forces try to assume control of much of the country from coalition forces on a rushed timeline, ahead of the scheduled withdrawal of most of coalition forces by December 2014.
"As we pledged, our forces have transitioned Nirkh district to Afghan national security forces and they have now assumed full responsibility for security in this key district," Gen. Joseph Dunford, the top commander of U.S. and NATO forces in Afghanistan, said in a statement released Saturday.
"The rest of Wardak will continue to transition over time as Afghan forces continue to grow in capability and capacity," he added.
Maj. Gen. Tony Thomas, the top U.S. special operations commander in Afghanistan, told The Associated Press in an interview that the transition of authority took place Saturday. "What it means is we brought in an Afghan special forces team to take the place of ours," Thomas said.
Attaullah Khogyani, spokesman for the governor of Wardak province outside Kabul, confirmed that U.S. special operations forces withdrew and were replaced by a joint Afghan security forces team.
Karzai had originally demanded the U.S. special operations forces pull out from the entire province, a gateway and staging area for Taliban and other militants for attacks on the capital Kabul. But he scaled down his demands to just the single district after negotiations with Dunford and other U.S. officials.
"President Karzai was specific, it's only for Nirkh, that was a provocative point," Thomas said. "American special operations forces are integral in the defense of Wardak from now until the foreseeable future."
U.S. commandos will also continue to visit the Afghan team in Nirkh.
"We're going to support them from a distance," Thomas said. "The reality is there was such a groundswell of support (from locals) in Wardak after the initial allegations that we're keeping several teams down there to work with the Afghan security forces for the future, with an idea that we'll transition over time."
The American special operations troops are paired with and live alongside locally recruited and trained teams known as Afghan local police. Thomas said most of the local police will be paired with Afghan security forces by the end of the summer, with the Americans making occasional visits as they will do in Nirkh, to assess whether they need logistic or other support.
One Wardak government official expressed relief that the agreement crafted with Karzai did not mean the complete pullout of U.S. forces from the province, saying that local officials were worried their new forces would not yet be able to keep hardcore insurgents out of the area.
The official spoke on condition of anonymity because his comments run counter to public statements made by Karzai that the Afghan security forces are ready for complete independence in Wardak.
Meanwhile, Taliban militants attacked a police convoy Saturday morning in Ghazni province in eastern Afghanistan, kicking off a fierce gunbattle, according to deputy provincial police chief Col. Mohammad Hussain.
The police requested a coalition air strike, which hit the militants' position and killed 15 fighters but also wounded nine civilians including a woman and child, Hussain said. He did not report any police casualties.
___
Associated Press writer Rahim Faiez contributed to this report.
Follow Kimberly Dozier on Twitter at http://twitter.com/KimberlyDozier
Source: http://news.yahoo.com/us-commandos-hand-over-troubled-area-afghans-085617778.html
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Acoustic time delay could improve phased array systems
Mar. 29, 2013 ? Radar systems today depend increasingly on phased-array antennas, an advanced design in which extensive grids of solid state components direct signal beams electronically. Phased array technology is replacing traditional electro-mechanical radar antennas -- the familiar rotating dish that goes back many decades -- because stationary solid state electronics are faster, more precise and more reliable than moving mechanical parts.
Yet phased array antennas, which require bulky supporting electronics, can be as large as older systems. To address this issue, a research team from the Georgia Institute of Technology has developed a novel device -- the ultra-compact passive true time delay. This component could help reduce the size, complexity, power requirements and cost of phased array designs, and may have applications in other defense and communication areas as well.
The patent-pending ultra-compact device takes advantage of the difference in speed between light and sound, explained Ryan Westafer, a Georgia Tech Research Institute (GTRI) research engineer who is leading the effort. The ultra-compact device uses acoustic technology to produce a type of signal delay that's essential to phased-array performance; existing phased-array antennas use cumbersome electrical technology to create this type of signal delay.
"Most true time delay equipment currently uses long, meandering electromagnetic delay lines -- comparable to coaxial cable -- that take up a lot of space," Westafer said. "In addition, there are some time delay designs that utilize photonic technology, but they currently have size and functionality drawbacks as well."
The ultra-compact delay device uses acoustic delay lines that are embedded entirely within thin film materials. The component can be made thousands of times smaller than an electrical delay-line design, Westafer said, and it can be readily integrated on top of semiconductor substrates commonly used in radar systems.
A Critical Delay
In a phased array radar system, true time delays are necessary to assure proper performance of the many signal beam producing elements that make up the array. As the elements scan back and forth electronically at extremely high speeds, their timing requires extremely fine coordination.
"The individual antenna elements of a phased array appear to scan together, but in fact each element's signal has to leave up to a few nanoseconds later than its neighbor or the steered beam will be spoiled," explained Kyle Davis, a GTRI research engineer who is a team member. "These delays need to march down each element in the array in succession for a steered beam to be produced. Without correct time delays, the signals will be degraded by a periodic interference pattern and the location of the target will be unclear."
Traditional phased array systems use one foot of electrical delay line for each nanosecond of delay. By contrast, the Georgia Tech team's time-delay design consists of a thin-film acoustic component that's a mere 40 microns square. The tiny device can be readily integrated into the silicon substrate of a radar component, yet it provides the same delay as many feet of cable.
This size reduction is possible because of a simple fact of physics -- sound traveling through the air moves about 100,000 times more slowly than light. As a result, when an electromagnetic wave such as a radar signal becomes an acoustic wave, it slows down dramatically. In the case of the ultra-compact passive true time delay component, the acoustic area of the component furnishes a multi-nanosecond delay in the space of a few microns.
"Microwave acoustic delay lines actually date back to 1959, but our ultra-compact delay's small size represents a significant advance that should allow microwave acoustic delay lines to be manufactured and integrated much more readily," explained William Hunt, a professor in the Georgia Tech School of Electrical and Computer Engineering. "And it's worth noting that this innovative work took place as the result of both strong student participation and very effective collaboration across several Georgia Tech units."
Acoustic Wave Conversion
A phased array radar using the Georgia Tech time delay component could operate like this: An electromagnetic wave is transmitted through an electrical line to the compact time delay device. Then, within the delay device, a piezoelectric transducer converts electromagnetic waves to acoustic waves, and over the distance of a few microns the waves are slowed by several orders of magnitude.
Once the required delay is achieved, the acoustic waves are transduced back to electromagnetic waves, delivered into another electrical line and transmitted by an antenna. A similar but reverse sequence takes place when the radar beam bounces back from its target and is received by the antenna.
In addition to Westafer, Davis and Hunt, the Georgia Tech development team includes GTRI principal research engineers Jeff Hallman and Jim Maloney; GTRI research engineer Brent Tillery and GTRI research associate Chris Ward; School of Electrical and Computer Engineering student Stephen Mihalko, and GTRI student assistant Jonathan Perez.
To date, the Georgia Tech team has successfully demonstrated that the current version of the ultra-compact passive true time delay can handle radar signals at 100 percent bandwidth while delivering a 10 nanosecond delay. The team is presently addressing technical issues such as signal loss, and near-term plans call for the demonstration of an improved device design and the delivery of initial packaged devices to customers.
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Clean fuel regulations: EPA, oil industry vie over effect on gas prices
EPA on Friday proposed new regulations to require refineries to make cleaner gasoline. The cost? EPA says less than a penny a gallon. Oil industry says nine cents a gallon ? and higher gas prices.
Suzanne Meredith, of Walpole, Mass., gases up her car at a Gulf station in Brookline, Mass., July 2012. Reducing sulfur in gasoline and tightening emissions standards on cars beginning in 2017, as the Obama administration is proposing, would come with costs as well as rewards.
Steven Senne/AP/File
EnlargeThe Obama administration proposed on Friday new ? and more costly ? regulations of the refining industry to produce cleaner gasoline and clearer skies.
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If the new rules are implemented as scheduled in 2017, the Environmental Protection Agency (EPA) says, they will spare thousands of people from premature death and prevent respiratory problems in tens of thousands of children. The cost: on average less than a penny gallon.
Not so, says the oil industry, which has been battling the EPA over the proposed rules. The new rules will add as much as nine cents a gallon to the cost of making fuel and will produce ?ambiguous? results, says The American Petroleum Institute.?API, the industry?s lobbying arm in Washington, refers to the proposed new rules as part of a ?tsunami of regulations? the industry faces this year that could add as much as 65 cents to the cost of producing a gallon of fuel in the future.
Gasoline prices are politically sensitive. Consumers often know how much they have paid for a gallon of gasoline compared with their prior fill-up. When pump prices are rising, consumers grumble and, if prices get high enough, cut back on other discretionary purchases. As a result, economists refer to rising fuel prices as a tax on the economy.
But will Americans pay more for fuel and smile about if they believe it will result in cleaner air?
?Some will, but the majority won?t,? answers Tom Kloza, chief oil analyst at GasBuddy.com. ?There is a sense among a lot of people that we are entitled to cheaper fuel prices than the rest of the world.?
The proposed changes would make US standards the same as most of Europe, Japan, and South Korea, Mr. Kloza says. ?We would be joining 45 other countries with tougher fuel standards,? he says.
Republicans quickly attacked the proposed regulation. ?The Obama Administration is modeling our regulations after California, which has the worst economy in the nation, and today?s announcement is essentially a guaranteed energy tax hike and unfortunately is just one of many radical policies coming out of this Administration that will deal a heavy blow to middle-class families and small businesses,? said Rep. Steve Scalise of Louisiana, chairman of the Republican Study Committee, in a statement.??
In January, Greenberg Quinlan Rosner Research, often associated with Democratic issues, conducted what it termed a ?bipartisan survey? of 800 registered voters for the American Lung Association on whether Americans favored tougher fuel regulations and improved antipollution laws. It found 62 percent of voters supported new gasoline and vehicle standards, and 32 percent opposed them.
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The Weirdest Thing on the Internet Tonight: Old Portents & Hand-Out Hijinx
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Death toll at 18 in Tanzania building collapse
ZANZIBAR, Tanzania (AP) ? At least 18 people were killed when a building collapsed Friday in the Tanzania's largest city, Dar es Salaam, police said Saturday, as hopes dimmed of rescuing more survivors.
Poor equipment hampered efforts to rescue more than 60 people believed to be trapped under the rubble, said Police commissioner Meshak Saddik. At least 17 people, three seriously injured, were pulled out of the debris Friday.
Officials said constriction work on the building, located on one of the busiest streets in Tanzania's commercial center, was about to be completed and that the structure did not have tenants. Most of the people caught in the collapse of the 12-story building were laborers as well as those passing by or loitering nearby. Some witnesses said dozens of construction workers and food vendors were in the building when it collapsed Friday morning and that scores of children were playing soccer in a nearby playground. Others said more than 200 casual laborers and engineers worked on the building regularly.
Saddik said three engineers who worked on the building had been taken into custody for questioning. In recent years building collapses have become frequent in East African countries as some property developers bypass regulations to cut costs.
Dar es Salaam police have halted work on a 16-story building that was being built adjacent to the one that collapsed, saying the construction project needs to be reviewed. Both buildings have the same owner.
Source: http://news.yahoo.com/death-toll-18-tanzania-building-collapse-102928087.html
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Even graphene has weak spots
Mar. 28, 2013 ? Graphene, the single-atom-thick form of carbon, has become famous for its extraordinary strength. But less-than-perfect sheets of the material show unexpected weakness, according to researchers at Rice University in Houston and Tsinghua University in Beijing.
The kryptonite to this Superman of materials is in the form of a seven-atom ring that inevitably occurs at the junctions of grain boundaries in graphene, where the regular array of hexagonal units is interrupted. At these points, under tension, polycrystalline graphene has about half the strength of pristine samples of the material.
Calculations by the Rice team of theoretical physicist Boris Yakobson and his colleagues in China were reported this month in the American Chemical Society journal Nano Letters. They could be important to materials scientists using graphene in applications where its intrinsic strength is a key feature, like composite materials and stretchable or flexible electronics.
Graphene sheets grown in a lab, often via chemical vapor deposition, are almost neverperfect arrays of hexagons, Yakobson said. Domains of graphene that start to grow on a substrate are not necessarily lined up with each other, and when these islands merge, they look like quilts, with patterns going in every direction.
The lines in polycrystalline sheets are called grain boundaries, and the atoms at these boundaries are occasionally forced to change the way they bond by the unbreakable rules of topology. Most common of the "defects" in graphene formation studied by Yakobson's group are adjacent five- and seven-atom rings that are a little weaker than the hexagons around them.
The team calculated that the particular seven-atom rings found at junctions of three islands are the weakest points, where cracks are most likely to form. These are the end points of grain boundaries between the islands and are ongoing trouble spots, the researchers found.
"In the past, people studying what happens at the grain boundary looked at it as an infinite line," Yakobson said. "It's simpler that way, computationally and conceptually, because they could just look at a single segment and have it represent the whole."
But in the real world, he said, "these lines form a network. Graphene is usually a quilt made from many pieces. I thought we should test the junctions."
They determined through molecular dynamics simulation and "good old mathematical analysis" that in a graphene quilt, the grain boundaries act like levers that amplify the tension (through a dislocation pileup) and concentrate it at the defect either where the three domains meet or where a grain boundary between two domains ends. "The details are complicated but, basically, the longer the lever, the greater the amplification on the weakest point," Yakobson said. "The force is concentrated there, and that's where it starts breaking."
"Force on these junctions starts the cracks, and they propagate like cracks in a windshield," said Vasilii Artyukhov, a postdoctoral researcher at Rice and co-author of the paper. "In metals, cracks stop eventually because they become blunt as they propagate. But in brittle materials, that doesn't happen. And graphene is a brittle material, so a crack might go a really long way."
Yakobson said that conceptually, the calculations show what metallurgists recognize as the Hall-Petch Effect, a measure of the strength of crystalline materials with similar grain boundaries. "It's one of the pillars of large-scale material mechanics," he said. "For graphene, we call this a pseudo Hall-Petch, because the effect is very similar even though the mechanism is very different.
"Any defect, of course, does something to the material," Yakobson said. "But this finding is important because you cannot avoid the effect in polycrystalline graphene. It's also ironic, because polycrystals are often considered when larger domains are needed. We show that as it gets larger, it gets weaker.
"If you need a patch of graphene for mechanical performance, you'd better go for perfect monocrystals or graphene with rather small domains that reduce the stress concentration."
Co-authors of the paper are graduate student Zhigong Song and his adviser, Zhiping Xu, an associate professor of engineering mechanics at Tsinghua. Xu is a former researcher in Yakobson's group at Rice. Yakobson is Rice's Karl F. Hasselmann Professor of Mechanical Engineering and Materials Science and professor of chemistry.
The Air Force Office of Scientific Research and the National Science Foundation supported the work at Rice. The National Natural Science Foundation of China, the Tsinghua University Initiative Scientific Research Program and Tsinghua National Laboratory for Information Science and Technology of China supported the work at Tsinghua.
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Journal Reference:
- Zhigong Song, Vasilii I. Artyukhov, Boris I. Yakobson, Zhiping Xu. Pseudo Hall?Petch Strength Reduction in Polycrystalline Graphene. Nano Letters, 2013; : 130325121321001 DOI: 10.1021/nl400542n
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Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.
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If World Cup draw was today ...
Let me pre-empt your comment and acknowledge: I know this is completely pointless. And in a way,?that?is the point.
I want to embrace the absurdity of looking too deep into early qualifying results. I want to see what the world would look like if Mexico kept struggling, Ghana didn?t get out of their group, or Portugal doesn?t track down Israel in Europe.
I want Uzbekistan?s name in draw, Venezuela in a finals, and nations like Montenegro and Bosnia-Herzegovina to breakthrough.
Most of all, I want some kind of reward for all of the international soccer we?ve been subjected to over the last five days. I want to know this is leading somewhere ? that these constant jumps from the club world into this alternative reality will be rewarded. The only way for my frustrated, fatigued little mind to grasp the implications is to draw out the 2014 World Cup.
So here?s what I did: I took the current standings from qualifying tournaments around the world, assumed the teams? points-per-game rates played out, and then ?qualified? the appropriate teams for Brazil. When playoffs were needed, I went with FIFA?s higher rated team (for no other reason than to take my preferences out of the equation).
Beyond using FIFA ranking as a tiebreaker, I didn?t assume the good teams would automatically make it. Think Panama?s going to fade? Too bad. They?re in first now. Montenegro?s not going to win their group? Then they won?t part of the last time we do this exercise eight months from now. We?re living in the present, baby. Embrace the now!
Once the 32 teams were decided. I pulled out Brazil and the seven seeded teams (by FIFA ranking), and conducted the draw by normal procedures. The way it ended up after playoffs, eight European teams formed one pot, the African and South American teams formed another, while the Asian and CONCACAF teams formed the last.
And this is how it played out.
AGAIN, this is not meant to be anything other than a fun exercise. I don?t intend it to be predictive or in any way a reflection of anybody?s analysis. It?s just a goof.
| Group A | Group B |
|---|---|
| Brazil France Cote d?Ivoire South Korea | Spain Switzerland Algeria Uzbekistan |
| Group C | Group D |
| England Greece Zambia Honduras | Italy Croatia Venezuela United States |
| Group E | Group F |
| Netherlands Belgium Chile Panama | Germany Russia Ecuador Australia |
| Group G | Group H |
| Colombia Montenegro Nigeria Japan | Argentina Bosnia and Herzegovina Tunisia Costa Rica |
Perhaps once we?re further down the qualifying road we can put some analysis in this space, but we?re still a little too far down the road to be taking this too seriously. For now, it?s cool to seem some of the new names and potential groups ?
? but for now, I leave the analysis to you.
Source: http://prosoccertalk.nbcsports.com/2013/03/27/world-cup-2014-draw/related/
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CA-BUSINESS Summary
Record Wall Street boosts sentiment, U.S. holds key in Q2
TOKYO (Reuters) - Whether the world's largest economy can sustain momentum will be a primary focus for investors for the next three months after a general recovery trend in the United States helped risk sentiment for broad markets in the first quarter of 2013. Asian shares edged higher and the euro steadied on Friday after banks in Cyprus reopened to relative calm. Overall trade was subdued, with many Asian markets, including Australia, Singapore and Hong Kong, closed on Friday for Easter holidays.
Banks lift TSX on Cyprus calm; index up for quarter
TORONTO (Reuters) - Canada's main stock index powered ahead in a late surge on Thursday, led by strength in financial and industrial shares, on relief that banks in Cyprus reopened relatively smoothly following a bailout deal. The market received further support from BlackBerry
More trouble for Cohen's SAC Capital as Steinberg indicted in NY
(Reuters) - U.S. prosecutors on Friday charged Michael Steinberg, a veteran portfolio manager at Steven A. Cohen's hedge fund, with insider trading in two technology stocks, the most senior SAC Capital Advisors' employee to be indicted in the government's long-running probe. FBI agents arrested Steinberg at his Park Avenue home in New York City at around 6 a.m. EDT (1000 GMT). Steinberg, wearing a blue sweater, pleaded "not guilty" to charges of securities fraud and conspiracy to commit securities when he appeared at a late morning arraignment.
Chesapeake names Dixon interim CEO as McClendon set to leave
(Reuters) - Chesapeake Energy Corp
Loeb's Third Point outperforms hedge fund rivals again
BOSTON (Reuters) - Hedge fund manager Daniel Loeb outperformed his rivals again in the first quarter with returns that kept pace with the stock market's recent rally, a person familiar with Loeb's returns said. The New York-based manager told investors late on Thursday that his flagship Third Point Offshore Fund rose 2.8 percent in March while the Third Point Ultra fund, the leveraged version of the Offshore fund, gained 4.2 percent.
Big depositors in Cyprus to lose far more than feared
NICOSIA (Reuters) - Big depositors in Cyprus's largest bank stand to lose far more than initially feared under a European Union rescue package to save the island from bankruptcy, a source with direct knowledge of the terms said on Friday. Under conditions expected to be announced on Saturday, depositors in Bank of Cyprus
Fiat CEO probed for violation of workers' rights
MILAN (Reuters) - Fiat's
Exclusive: Indonesia's CT Corp proposes all-cash deal for Bakrie's media unit
TANJUNG BENOA, Indonesia (Reuters) - Indonesia's fifth-richest man has proposed to buy a controlling stake in PT Visi Media Asia, valued at up to $1.8 billion, in an all-cash deal that would give him the lion's share of the TV advertising market in Southeast Asia's biggest economy. Chairul Tanjung, the billionaire founder and chairman of CT Corp, a conglomerate with banking and media interests, told Reuters that his company wanted to buy the stake in the media unit of Indonesia's powerful Bakrie family without any partners.
Deutsche Bank probe finds incomplete data given to prosecutors: magazine
FRANKFURT (Reuters) - An internal investigation at Deutsche Bank
Power firm CEZ files complaint with EU against Bulgaria
PRAGUE (Reuters) - Czech power producer CEZ
Source: http://news.yahoo.com/ca-business-summary-012952632--finance.html
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Friday, March 29, 2013
the causes and effects of phobia in mathematics ... - information library
A RESEARCH PROJECT SUBMITED TO NATIONAL TEACHER?S INSTITUTE, KADUNA
IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF A POST GRADUKATE DIPLOMA (PGD) IN EDUCATION
CHAPTER ONE
INTRODUCTION
1.1???????????? BACKGROUND TO THE STUDY:
Mathematics can be defined as the science of number and space and the language of science and technology. It is an essential requirement by every field of intellectual Endeavour and human development to cope with the challenges of life.? Mathematics can also be defined as the
queen and servant of all the school subjects since it cut across the school curricula. It is equally seen as the language used to describe the problems arising in technology.? It relates other school subjects in areas like number and numeration, variations, graphs, fractions, solution of equation, and areas and volumes.Brief history of the formal teaching of mathematics in Nigeria Started with Arithmetics a component of mathematics at the primary and postprimary schools Fajemidagba (1999), according to him, Arithmetics was compulsory for every primary school pupils and must be passed before a pupil? could obtain the ?Primary school leaving certificate,? the same condition holds for the Teacher Training Colleges either grade II or III. ??After the launching of the Sputnik, the first earth Satellite in space in November 1957 by the Russians, which according to Griffiths and Howson (1974) has an enormous effects on American Complacency about superiority in engineering capability over that of Russians.? The result of the doubt were series of hot debates and arguments on the suitability or otherwise of the school mathematics and curricula.? These occurrences were called ?issues and forces?: behind the reformation of school mathematics Curricula Contents, which also affect various reforms in school Mathematics programme in Nigeria. The reformation of mathematics curricula has continued to evolve considering its enormous importance to the development of the world. Mathematics still remains one of the core and compulsory subjects for the Nigerian students at both primary and post primary schools. Recently, mathematics has become a determining factor to gaining admission into most Nigerian universities as it must be passed up to credit level before one gains admission.? ?
In spite of its importance to the students? advancement in academics, many students dread mathematics. Given the right to chose, many secondary school students would outrightly avoid mathematics, this is because?? many of them have developed some elements of fears about the subject, may be, as a result of long time negative information they get every year about the poor and low level performance in WAEC and NECO examinations in Mathematics or other factors this research work sets?? out to unravel. According to Ajagun (2000) the performance of students in both junior and senior secondary science in Nigeria has remained an issue of concern to all stakeholders.
Dwelling more on the fear of mathematics by the secondary school students, psychologytoday.com defines? fear as a vital response to physical and emotional danger? if we didn?t feel it, we couldn?t protect ourselves from the?? legitimate threats.? Toscany Academy (2012) This quote can be translated in the context of threat posed by mathematics to the candidates preparing for the examination.? Since most of these students have lost hope and psychologically? defeated due to fear, this affect their level of interest and passion in the subject and the greater percentage of students opt for examination malpractices and resort to external help.? We all know that fear is learnt, ?a burnt child dreads fire? is a saying we often use showing that a child learns from his/her?? experiences.? Fear is also contagious as children learn fear from observing other show fears.?? Children also learn fear from their contemporaries.
Phobia in the other hand is a clinical or pathologically intense fear often irrational leading to a compulsive need to avoid a thing or event.
(NTI PDE 102:187) the term ?Phobia? in an everyday life can be used to refer to fears which have rational?? origin. When?? fear reaches an extreme pitch, it becomes a phobia. The? implication? of the above in? a child is,? if?? failure is greeted?? with scolding and corporal? punishment with little attention? to? motivation, clarity and? relevance, student? will? dislike to learn a particular subject.? When experience of learning becomes so unpleasant, it creates the emotions of fear and boredom. In such situation,?? even the brightest pupils will fail to profit?? from learning (NTI, PDE 102)?
1.2? STATEMENT?? OF THE PROBLEM
The lackadaisical attitude of the?? students?? towards mathematics in our secondary school has reached such an extreme pitch, that every lover of education, growth and development of Nigeria cannot afford to keep mute on the happenings in the mathematics education.? Ajagun (2000) decried ?the?? performance of students in both junior and senior secondary science has remained an issue of concern to all the stakeholders. The overwhelming personal observation on? the types of students? found in science classes of our?today- secondary schools in? Nigeria can be better? imagined than? to engage as ones students. In?? the past, we used to have brilliant? students in sciences,? if that? is true,? it implies that something has gone? wrong somewhere, either that our students? do not work? hard again, or? they have been overtaken by fear of some of? these? subjects. Fear as we all know is learnt?? and it is contagious and?? dangerous. It may have struck our students into avoidance of mathematic.
Phobia has been defined as a clinical or pathologically intense fear often irrational leading to a compulsive need to avoid an event or thing. Personal observation has also revealed that many a student?? would desert or dodge mathematics class just? before?? the? arrival of?? the teacher and?? during the examination he/she?? struggles? to pass at all cost. It is? against? these ugly trend and background ?that the? researcher sets out to? investigate? some of the causes and? effects of? phobia in? mathematics among secondary school students in Abakaliki?? Local? Government? Area? with a view to? allaying the fear in our students? and? to better position them with right? disposition for active? learning of mathematics.
1.3 PURPOSE OF THE STUDY?
The general purpose of this study is to investigate the possible causes and effects of students? phobia in mathematics as? regards to implications and?? threats posed to the development of our country Nigeria and the developments of science and technology.
The specific purpose of this study is derived from the general purpose?? stated above, these include the following:
i.??????????????????? ?To x-ray the causes of phobia? in? mathematics amongst the secondary school students in Abakaliki Local Government? Area?
ii.???????????????? To investigate the effects of this phobia in?? mathematics? on the students performance in both internal and external examination
iii.?????????????? To find out how teaching techniques and instructional materials would improve the lukewarm attitudes of students towards ??mathematics.
iv.?????????????? To access the? impact of ??phobia in? mathematics to the development of science and technology Nigeria
1.4 SIGNIFICANCE OF THE STUDY?
This study is of immense significant as the findings would use in the following ways:
i.??????????????????? ?To help students overcome the unnecessary that has hampered from effective learning of mathematics in our secondary schools.
ii.???????????????? To help?? the students? improve on their?? performances in mathematics and? other science subjects ?
iii.?????????????? The prevalent cases of? examination malpractices amongst the secondary ?school students especial in? mathematics would?? be reduced to? the? barest? minimal
iv.?????????????? It will equally help to improve on? the? number of candidates wishing?? to make? career in mathematics in our tertiary? institutions
v.????????????????? The Nigerian government stands to benefit?? from this research work in the aspect of positioning the?? country as a technological and industrialized nation since the bedrock of science and technology is mathematics. Again?? the guest for??? self ?reliance and self ?employment to the teeming youths will find solutions in this research work.
1.5 SCOPE OF THE STUDY
This research project will only explore on the causes and effects of phobia in mathematics amongst the secondary school students in Abakaliki Local Government Area only. Nevertheless, it would have been ideal enough to carryout?? this research in the whole of Ebonyi State and Nigeria at large so as to reach an irrevocable conclusion on the matter, but for time and financial constraints.? The?? questionnaire and interview will? be structured to cover? only ten secondary schools? in? Abakaliki? Local? Government Area? and the content? would span on the causes of phobia in mathematics, the consequences of phobia? in the? students performance in both internal and external examinations.? It will equally harness the best teaching techniques and instructional materials for??? the effective learning and?? lesson delivery. The importance of?? mathematics to the national development?? will be brought to bare.?
1.6 RESEARCH? QUESTIONS
In the course of carrying out this project work, the following questions have been formulated to provide the needed information to achieve the set?? objectives of this study; namely
1.????? What are the cases of phobia in mathematics among?? the students of secondary schools, in Abakaliki?
2.????? What effects do you think phobia in mathematics has in the performance of students in both internal and external examinations?
3.????? ?What impact has phobia in mathematics on the national development?
Related Posts: MATHEMATICS, TVE
Source: http://martinslibrary.blogspot.com/2013/03/the-causes-and-effects-of-phobia-in.html
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