Mar. 27, 2013 ? A computer model provides important clues for the production of tightly packed electronic components.
Greater numbers of ever-smaller components are required to fit on computer chips to meet the ongoing demands of miniaturizing electronic devices. Consequently, computer chips are becoming increasingly crowded. Designers of electronic architectures have therefore followed the lead of urban planners and started to build upward. In so-called 'three-dimensional (3D) packages', for example, several flat, two-dimensional chips can be stacked on top of each other using vertical joints.
Controlling the properties of these complex structures is no easy task, as many factors come into play during production. Faxing Che and Hongyu Li and co-workers from the A*STAR Institute of Microelectronics, Singapore, have now developed a powerful modeling method that allows large-scale simulations -- and optimization -- of the fabrication process, which provides welcome assistance to designers.
Among the challenges of producing tightly packed computer chips is the need to prevent warpage of the underlying silicon wafer as electronics components are stacked on it. Warpage leads to a number of unwanted effects. "Strong warpage can cause wafer breakage, it makes tight packing more difficult and some processing machines cannot handle high-warpage wafers," explains Li. The degree of warpage depends on many design and process parameters, and optimizing the procedure experimentally is time-consuming and costly.
Using their computer model, Che and Li studied a wide range of parameters that influence the warpage of an 8-inch diameter silicon wafer. They focused, in particular, on how a silicon substrate responds to the deposition of layers of copper -- through which electrical currents eventually flow. "This is the first time that a model has been able to predict warpage [at] the level of the entire wafer," says Li. Moreover, the stress on the wafer can be determined accurately. The calculated values agreed well with experimental data. Importantly, with the computer simulations, the researchers could explore regimes that cannot be easily studied experimentally, such as how the depth of the connections between layers influences wafer warpage.
The next goal is to simulate even larger wafers with variable connection sizes, explains Li. "Today, there are two industry standards for 3D packaging applications, 8-inch and 12-inch wafers, but the latter are becoming increasingly important," she says. The team's model is applicable to these larger wafers, too, but it requires optimization. Currently, Che, Li and their co-workers are collecting warpage and stress data for 12-inch wafers. They will use these data for developing their model further, according to Li.
The A*STAR-affiliated researchers contributing to this research are from the Institute of Microelectronics
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The above story is reprinted from materials provided by The Agency for Science, Technology and Research (A*STAR).
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Journal Reference:
Faxing Che, Hongyu Y. Li, Xiaowu Zhang, Shan Gao, Kenghwa H. Teo. Development of Wafer-Level Warpage and Stress Modeling Methodology and Its Application in Process Optimization for TSV Wafers. IEEE Transactions on Components, Packaging and Manufacturing Technology, 2012; 2 (6): 944 DOI: 10.1109/TCPMT.2012.2192732
Note: If no author is given, the source is cited instead.
Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.
WASHINGTON (AP) ? The U.S. has taken its first real swipe at China following accusations that the Beijing government is behind a widespread and systemic hacking campaign targeting U.S. businesses.
Buried in a spending bill signed by President Barack Obama on Tuesday is a provision that effectively bars much of the federal government from buying information technology made by companies linked to the Chinese government.
It's unclear what impact the legislation will have, or whether it will turn out to be a symbolic gesture. The provision only affects certain non-defense government agency budgets between now and Sept. 30, when the fiscal year ends. It also allows for exceptions if an agency head determines that buying the technology is "in the national interest of the United States."
Still, the rule could upset U.S. allies whose businesses rely on Chinese manufacturers for parts and pave the way for broader, more permanent changes in how the U.S. government buys technology.
"This is a change of direction," said Stewart Baker, a former senior official at the Homeland Security Department now with the legal firm Steptoe and Johnson in Washington. "My guess is we're going to keep going in this direction for a while."
Rep. Dutch Ruppersberger of Maryland, the top Democrat on the House Intelligence Committee, said he supports the restriction and doesn't think it would be too cumbersome for federal agencies. The Defense and Energy departments already are mindful of how its networks are built.
"Anything we can do to call awareness to the fact that we're continuing to be cyberattacked, we're continuing to lose jobs, and that billions of dollars in American money is being stolen," Ruppersberger said in an interview Wednesday.
In March, the U.S. computer security firm Mandiant released details on what it said was an aggressive hacking campaign on American businesses by a Chinese military unit. Since then, Treasury Secretary Jacob Lew has used high-level meetings with Beijing officials to press the matter. Beijing has denied the allegations.
Congressional leaders have promised to push comprehensive legislation that would make it easier for industry to share threat data with the government. But those efforts have been bogged down amid concerns that too much of U.S. citizens' private information could end up in the hands of the federal government.
As Congress and privacy advocates debate a way ahead, lawmakers tucked "section 516" into the latest budget resolution, which enables the government to pay for day-to day operations for the rest of the fiscal year. The provision specifically prohibits the Commerce and Justice departments, NASA and the National Science Foundation from buying an information technology system that is "produced, manufactured or assembled" by any entity that is "owned, operated or subsidized" by the People's Republic of China.
The agencies can only acquire the technology if, in consulting with the FBI, they determine that there is no risk of "cyberespionage or sabotage associated with the acquisition of the system," according to the legislation.
The move might sound like a no-brainer. If U.S. industry and intelligence officials are right, and China is stealing America's corporate secrets at a breathtaking pace, why reward Beijing with lucrative U.S. contracts? Furthermore, why install technical equipment that could potentially give China a secret backdoor into federal systems?
Last fall, Ruppersberger and House Intelligence Committee Chairman Mike Rogers, R-Mich., released a report urging U.S. companies and government agencies to drop any business with Chinese telecommunications companies Huawei Technologies Ltd. and ZTE Corp. because of the security risks they pose.
"Any bug, beacon or backdoor put into our critical systems could allow for a catastrophic and devastating domino effect of failures throughout our networks," Rogers said in a statement accompanying the report.
But a blanket prohibition on technology linked to the Chinese government may be easier said than done. Information systems are often a complicated assembly of parts manufactured by different companies around the globe. And investigating where each part came from, and if that part is made by a company that could have ties to the Chinese government could be difficult.
Huawei, the third-largest maker of smartphones, says it is owned by its employees and rejects claims that it is controlled by the communist government or China's military.
Depending on how the Obama administration interprets the law, Baker said it also could cause problems for the U.S. with the World Trade Organization, whose members include U.S. allies like Germany and Britain that might rely on Chinese technology to build computers or handsets.
But in the end, Baker says it could make the U.S. government safer and wiser.
"We do have to worry about buying equipment from companies that may not have our best interests at heart," he said.
___
Follow Anne Flaherty on Twitter at https://twitter.com/AnneKFlaherty.
By Martyn Herman LONDON, March 28 (Reuters) - Whether by design, necessity, self-interest or because of all three, nurturing youngsters has become fashionable for England's elite with no expense spared in the hunt for the new Wayne Rooney or Steven Gerrard. The length and breadth of the country, scouts from top clubs are hoovering up promising footballers barely old enough to tie their bootlaces in a bid to unearth the 30 million pounds ($45.40 million) treasures of the future. ...
Insurance companies will have to pay more for medical claims on individual health policies under President Barack Obama's overhaul, says a new report by the Society of Actuaries.
By Ricardo Alonso-Zaldivar,?Associated Press / March 26, 2013
President Barack Obama signs the health care bill in Washington, March 23, 2010. Medical claims costs, the biggest driver of health insurance premiums, will jump an average 32 percent for individual policies under President Barack Obama?s overhaul, according to a study by the nation?s leading group of financial risk analysts.
J. Scott Applewhite / AP / File
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Insurance companies will have to pay out an average of 32 percent more for medical claims on individual health policies under President Barack Obama's overhaul, the nation's leading group of financial risk analysts has estimated.
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That's likely to increase premiums for at least some Americans buying individual plans.
The report by the Society of Actuaries could turn into a big headache for the Obama administration at a time when many parts of the country remain skeptical about the Affordable Care Act.
While some states will see medical claims costs per person decline, the report concluded the overwhelming majority will see double-digit increases in their individual health insurance markets, where people purchase coverage directly from insurers.
The disparities are striking. By 2017, the estimated increase would be 62 percent for California, about 80 percent for Ohio, more than 20 percent for Florida and 67 percent for Maryland. Much of the reason for the higher claims costs is that sicker people are expected to join the pool, the report said.
The report did not make similar estimates for employer plans, the mainstay for workers and their families. That's because the primary impact of Obama's law is on people who don't have coverage through their jobs.
The administration questions the design of the study, saying it focused only on one piece of the puzzle and ignored cost relief strategies in the law such as tax credits to help people afford premiums and special payments to insurers who attract an outsize share of the sick. The study also doesn't take into account the potential price-cutting effect of competition in new state insurance markets that will go live on Oct. 1, administration officials said.
At a White House briefing on Tuesday, Health and Human Services Secretary Kathleen Sebelius said some of what passes for health insurance today is so skimpy it can't be compared to the comprehensive coverage available under the law. "Some of these folks have very high catastrophic plans that don't pay for anything unless you get hit by a bus," she said. "They're really mortgage protection, not health insurance."
A prominent national expert, recently retired Medicare chief actuary Rick Foster, said the report does "a credible job" of estimating potential enrollment and costs under the law, "without trying to tilt the answers in any particular direction."
"Having said that," Foster added, "actuaries tend to be financially conservative, so the various assumptions might be more inclined to consider what might go wrong than to anticipate that everything will work beautifully." Actuaries use statistics and economic theory to make long-range cost projections for insurance and pension programs sponsored by businesses and government. The society is headquartered near Chicago.
Kristi Bohn, an actuary who worked on the study, acknowledged it did not attempt to estimate the effect of subsidies, insurer competition and other factors that could mitigate cost increases. She said the goal was to look at the underlying cost of medical care.
"Claims cost is the most important driver of health care premiums," she said.
"We don't see ourselves as a political organization," Bohn added. "We are trying to figure out what the situation at hand is."
Salivating haters can go ahead and close their gaping mouths on this one. The stories of Justin running amok in his neighborhood, threatening people are starting to sound a little exaggerated. There is nothing more the troll-infested new media likes more than a fallen star. In this case, the boy who started as a viral online wonder has been going through some changes. His thick eyebrows and boyish face have taken a backseat, and his outlandish driving and temper have taken the fore front. But what exactly has been going on? It began with a video of him yelling at a pap who apparently swarmed him on his way to his car. It was a side of Justin that even his obsessive Tween fans didn’t want to believe. It seemed only weeks before we started hearing about another allegedly violent run-in, this time with a neighbor. The original story goes that he got a really sweet Ferrari delivered to his house, then decided to take it for a spin. One particular neighbor who has young kids wasn’t happy about what he says was a 100MPH joyride through the streets. He supposedly went onto Justin’s property and started giving him a [...]
A sense of adventure does not diminish with age. As older women, we have a greater sense of self, are more confident and appreciate those things that are most important in life. We are inspired by natural and authentic beauty, have a dedication to lifelong learning and a curiosity to explore new experiences. Above all, we appreciate and stand in awe of the wonders our world holds. The following 6 must-see tours are suggestions for women just like us. If you have an adventure travel experience you?d like to share, please comment below.
Failte, Ireland ? the Most Beautiful Place on Earth!
National Geographic Photographers dubbed Southern Ireland?s Dingle Peninsula The Most Beautiful Place on Earth thanks to breathtaking views and pristine archeological sites. This unique area of Ireland has supported life for over 6,000 years, and the landscape is dotted with over 2,000 castles, strongholds and archaeological monuments.
Begin your morning with a horseback ride along pristine beaches, four wheeling through the hills or hiking ancient walking trails that lead you through greenest hills you?ve ever seen. Take a mid-morning tour of haunted sites with a special interest tour leader who will fill you in on local legends and lore while giving you a truly unique tour. Try your hand at archery or skeet shooting on castle grounds before ending your tour mid-afternoon.
Take a surfing or try kayaking lesson in the afternoon, charter a vessel for deep sea fishing fun or try dropping a line into one of the many rivers along the coast. Complete your day with Ireland?s finest cuisine accompanied by Irish brewed stouts or ales at a local pub, where you?re sure to have an unbelievable evening full of laughter, storytelling and music.
Anchorage (Alaska),?U.S.A.?- Flightseeing Tours
Alaska is the final frontier, and there is no better place to experience such a ruggedly beautiful terrain while still being within reach of the conveniences of the city. Anchorage is snuggled into the Chugach Mountain Range and receives 600 inches of snow every winter. One of the best ways to view majestic Chugach State Park without undertaking a mountain climbing adventure is to hop aboard a flightseeing tour.
During your tour of the Alaskan skies, you will travel over the Knik Glacier rim where you will view amazing hanging glaciers. Zip over the Colony Glacier at Lake George to view where it spills into the winding Knik Glacier Gorge. See moose, Dall sheep, and more while you fly over pristine lakes and surrounded by breath-taking snowcapped mountains before heading back to your hotel or private cabin.
South Africa ? Elephant Back Safaris
Follow the footsteps of the Ancients to a land of magnificent beauty and exotic wildlife.
Jeep safaris rarely stray from the road, but an elephant back safari takes you off the beaten track. Your tour begins in the saddle of Africa?s most beloved transportation: the elephant. Because their scent masks yours, other creatures feel safe. You?ll remain safe and protected while viewing Africa through the elephant?s eyes ? complete with lions, tigers, hippos, rhinos and more.
Be inspired when you meet preserve guardsmen with passion, sacrifice and dedication to animal welfare. Guards are community heroes: military tough, attuned to the environment, and uniquely qualified by skills learned only by native tribesmen as a rite of passage.
Return to civilization, where you are welcome to tour local markets brimming with handmade textiles, jewelry, art, instruments and traditional dress while you watch the natives sporadically break out in song and dance. This trip is hard to top!
Seattle (WA), U.S.A.?- Blake Island Boat Tour
The appreciation of stunning outdoor beauty combined with a peek into the world of ancient civilizations equates to an adventure tour you don?t want to miss. Seattle?s Puget Sound is home to Blake Island, a private island accessible only by private charter or boat. Hop on your cruise boat from downtown Seattle?s Pier 55, where you will cruise to Tillicum Village.
Tourists learn about the ways of ancient inhabitants while being greeted with a traditional meal of steamed clams in nectar and salmon prepared in Native style. Take in a show of the Coast Salish tribe?s storytelling and symbolism before wrapping up with a quick tour of the islands. Explore the island?s walking and hiking trails and 5 miles of pristine beaches before wrapping up your tour at the gift shop.
Cambodia ? Jungle Safari and Boat Tour
Many of Cambodia?s most precious sites were abandoned for unknown reasons. In time, they were forgotten, eventually lost to the jungle, where they lay untouched, slowly disintegrating. Political unrest discouraged archaeological work. Today, the political climate is comfortable, rediscovery efforts are supported, and there is much to see. While you?re sure to visit Cambodia?s temples and sites, there are adventures to be had in the jungle and sea!
Your adventure begins with breakfast aboard a converted Khmer tour boat. While traveling to Koh Ta Kiev, you?ll enjoy views of lush jungles and white sand beaches complemented by brilliantly blue water. Snorkel stunningly colorful coral reef and try your hand at fishing for squid and reef fish. You will dock on a secluded island before lunching on traditionally cooked fresh seafood at a Khmer floating fishing village. Be sure to explore the local markets for one-of-a-kind souvenirs.
Cruise north to a private cove, drop anchor and take a 30 minute guided jungle trek, where you will likely see jungle cats, exotic birds, monkeys, snakes and other native wildlife. Take a quick dip before leaving campers around 4pm, or speak with your tour guide about renting tent space for an overnight stay in the jungle. Your tour comes to a close with your boat ride back to the mainland whistle you enjoy a sunset drink.
Austin (TX), U.S.A. ? Lake Travis Zip Line Adventures
Austin is a great place to vacation when cold weather keeps beating you back indoors. Temperatures are warm year round, and the city offers constant musical entertainment, numerous fishing lakes, natural hot springs and more to enjoy at your leisure.
While leisure is great, if you?re looking for something a little more heart-poundingly adventurous, you?ve got to try the safe but thrilling 2 ? hour zip line tour of the famous canyons and inlets gracing Lake Travis. Fly down 5 different zip lines ranging in length from 250 feet to over 2800 feet. You?ll never experience views like these any other way! Professional tour guides teach you about the local area while assisting you through challenging hikes and nature walks.
Have you ever participated in an adventurous tour? Did it change your life? What was your experience and what tips would you give to your fellow travelers? Please add your comments below?
New system to restore wetlands could reduce massive floods, aid cropsPublic release date: 27-Mar-2013 [ | E-mail | Share ]
Contact: Meghna Babbar-Sebens meghna@oregonstate.edu 541-737-8536 Oregon State University
CORVALLIS, Ore. Engineers at Oregon State University have developed a new interactive system to create networks of small wetlands in Midwest farmlands, which could help the region prevent massive spring floods and also retain water and mitigate droughts in a warming climate.
The planning tool, which is being developed and tested in a crop-dominated watershed near Indianapolis, is designed to identify the small areas best suited to wetland development, optimize their location and size, and restore a significant portion of the region's historic water storage ability by using only a small fraction of its land.
Using this approach, the researchers found they could capture the runoff from 29 percent of a watershed using only 1.5 percent of the entire area.
The findings were published in Ecological Engineering, a professional journal, and a website is now available at http://wrestore.iupui.edu/ that allows users to apply the principles to their own land.
The need for new approaches to assist farmers and agencies to work together and use science-based methods is becoming critical, experts say. Massive floods and summer droughts have become more common and intense in the Midwest because of climate change and decades of land management that drains water rapidly into rivers via tile drains.
"The lands of the Midwest, which is one of the great food producing areas of the world, now bear little resemblance to their historic form, which included millions of acres of small lakes and wetlands that have now been drained," said Meghna Babbar-Sebens, an assistant professor of civil and construction engineering at Oregon State. "Agriculture, deforestation, urbanization and residential development have all played a role.
"We have to find some way to retain and slowly release water, both to use it for crops and to prevent flooding," Babbar-Sebens said. "There's a place for dams and reservoirs but they won't solve everything. With increases in runoff, what was once thought to be a 100-year flood event is now happening more often.
"Historically, wetlands in Indiana and other Midwestern states were great at intercepting large runoff events and slowing down the flows," she said. "But Indiana has lost more than 85 percent of the wetlands it had prior to European settlement."
An equally critical problem is what appears to be increasing frequency of summer drought, she said, which may offer a solid motivation for the region's farmers to become involved. The problem is not just catastrophic downstream flooding in the spring, but also the loss of water and soil moisture in the summer that can be desperately needed in dry years.
The solution to both issues, scientists say, is to "re-naturalize" the hydrology of a large section of the United States. Working toward this goal was a research team from Oregon State University, Indiana University-Purdue University in Indianapolis, the Wetlands Institute in New Jersey, and the U.S. Environmental Protection Agency. They used engineering principles, historic analysis and computer simulations to optimize the effectiveness of any land use changes, so that minimal land use alteration would offer farmers and landowners a maximum of benefits.
In the Midwest, many farmers growing corn, soybeans and other crops have placed "tiles" under their fields to rapidly drain water into streams, which dries the soil and allows for earlier planting. Unfortunately, it also concentrates pollutants, increases flooding and leaves the land drier during the summer. Without adequate rain, complete crop losses can occur.
Experts have also identified alternate ways to help, including the use of winter cover crops and grass waterways that help retain and more slowly release water. And the new computer systems can identify the best places for all of these approaches to be used.
###
The work has been supported by the Indiana State Department of Agriculture and the National Science Foundation.
Editor's Note: A digital image of Midwest wetlands is available online: http://bit.ly/YuMdUG
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New system to restore wetlands could reduce massive floods, aid cropsPublic release date: 27-Mar-2013 [ | E-mail | Share ]
Contact: Meghna Babbar-Sebens meghna@oregonstate.edu 541-737-8536 Oregon State University
CORVALLIS, Ore. Engineers at Oregon State University have developed a new interactive system to create networks of small wetlands in Midwest farmlands, which could help the region prevent massive spring floods and also retain water and mitigate droughts in a warming climate.
The planning tool, which is being developed and tested in a crop-dominated watershed near Indianapolis, is designed to identify the small areas best suited to wetland development, optimize their location and size, and restore a significant portion of the region's historic water storage ability by using only a small fraction of its land.
Using this approach, the researchers found they could capture the runoff from 29 percent of a watershed using only 1.5 percent of the entire area.
The findings were published in Ecological Engineering, a professional journal, and a website is now available at http://wrestore.iupui.edu/ that allows users to apply the principles to their own land.
The need for new approaches to assist farmers and agencies to work together and use science-based methods is becoming critical, experts say. Massive floods and summer droughts have become more common and intense in the Midwest because of climate change and decades of land management that drains water rapidly into rivers via tile drains.
"The lands of the Midwest, which is one of the great food producing areas of the world, now bear little resemblance to their historic form, which included millions of acres of small lakes and wetlands that have now been drained," said Meghna Babbar-Sebens, an assistant professor of civil and construction engineering at Oregon State. "Agriculture, deforestation, urbanization and residential development have all played a role.
"We have to find some way to retain and slowly release water, both to use it for crops and to prevent flooding," Babbar-Sebens said. "There's a place for dams and reservoirs but they won't solve everything. With increases in runoff, what was once thought to be a 100-year flood event is now happening more often.
"Historically, wetlands in Indiana and other Midwestern states were great at intercepting large runoff events and slowing down the flows," she said. "But Indiana has lost more than 85 percent of the wetlands it had prior to European settlement."
An equally critical problem is what appears to be increasing frequency of summer drought, she said, which may offer a solid motivation for the region's farmers to become involved. The problem is not just catastrophic downstream flooding in the spring, but also the loss of water and soil moisture in the summer that can be desperately needed in dry years.
The solution to both issues, scientists say, is to "re-naturalize" the hydrology of a large section of the United States. Working toward this goal was a research team from Oregon State University, Indiana University-Purdue University in Indianapolis, the Wetlands Institute in New Jersey, and the U.S. Environmental Protection Agency. They used engineering principles, historic analysis and computer simulations to optimize the effectiveness of any land use changes, so that minimal land use alteration would offer farmers and landowners a maximum of benefits.
In the Midwest, many farmers growing corn, soybeans and other crops have placed "tiles" under their fields to rapidly drain water into streams, which dries the soil and allows for earlier planting. Unfortunately, it also concentrates pollutants, increases flooding and leaves the land drier during the summer. Without adequate rain, complete crop losses can occur.
Experts have also identified alternate ways to help, including the use of winter cover crops and grass waterways that help retain and more slowly release water. And the new computer systems can identify the best places for all of these approaches to be used.
###
The work has been supported by the Indiana State Department of Agriculture and the National Science Foundation.
Editor's Note: A digital image of Midwest wetlands is available online: http://bit.ly/YuMdUG
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
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Public release date: 27-Mar-2013
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