Fifth Annual SWE Extreme Gingerbread House Competition

The Brown University Society for Women Engineers will be sponsoring its fifth annual "Extreme Gingerbread House Competition" on Friday, December 2, from 5:00 - 7:00 in the lobby of the Barus and Holley building on 184 Hope Street.

Twenty-two teams of 3-5 students and professors will be allowed to pre-register for the competition. Any additional teams that express interest will be placed on a waitlist in the event that a team does not arrive. If the team has not arrived within five minutes of the beginning of the event, their spot will be given to a team on the waitlist or a team that has shown up at the event without registering.

Each team will be supplied with two boxes of graham crackers, two Ziploc bags of royal icing, and a tray on which to construct their house. Additionally, all teams will be provided with an empty sandwich size Ziploc bag for taking the communal supplies. Foods such as candy canes, M&Ms, teddy grahams, shredded coconut, etc., will be kept on a central table. At the start of the one hour time slot of building, one member of each team will be allowed to take the empty Ziploc bag to the communal table and fill the bag with whatever supplies they feel are most valuable for their team’s house. All food items will be provided by SWE at the event; teams are NOT allowed to bring any of their own food.

The teams will have one hour to construct their houses out of the provided food. Houses should be designed to follow the criteria listed below:
- The house must fit on the provided tray and not cover the drilled-in holes.
- House dimensions must exceed 6”x6”x6”.
- The house must be hollow.
- The maximum wall thickness is 1”.
- The house must be glued/pasted to the tray; the house may not slide around the tray.
- The house should be designed to withstand earthquakes.

Teams are allowed to bring any tools that they think will be helpful such as knives, drills, etc. Teams are responsible for bringing the necessary power connections/extension cords. If you plan on using tools, please ensure you know how to use them safely and plan on bring the necessary personal protective equipment, such as safety glasses. No chemicals can be used during the manufacturing of the house; the house and all its contents must remain edible at all times.

After exactly one hour, the teams will be forced to stop construction on their houses. The houses will initially be judged before a panel of three faculty judges on (1) Attractiveness of the House [1-10 points] (2) Novel use of Building Materials [1-5 points] (3) Use of Available Space (ie decorations other than the house) [1-5 points]. Additionally, judges will have the option to select one “wildcard” house after viewing all the completed houses. Judges will award a bonus of three points to the house if they feel that one house was exceptional in a way that was not represented in the other scores; this is optional and at the judges discretion. The sum of these components will be used as the team’s aesthetic score.

The second portion of judging will be on the ability of the house to withstand a simulated earthquake. The tray will be attached to a shake table and cycled through a regimen moving from a low frequency to a high frequency. After every 15 seconds, the frequency will increase. Time will start when the shake table is turned on, and will be stopped when part of the house falls off the main structure; this includes decorations attached to the house, but not “environmental decorations” that are simply on the tray. The final call on whether a house has "failed" will be at the judges' discretion. Houses will not be judged until tables and floors are clean.

After all the houses have been tested, the maximum amount of time on the shake table to make a gingerbread house break will be used to calculate the scores, as shown below:

          GroupTime
----------------------- x 50 = Total
Maximum Group Time

Total group scores will be calculated by combining the aesthetic score (out of 25 points) and the stability score (out of 50 points) for a total score out of 75 points. The team with the most points will be considered the winner. The team with the second highest number of points will be given second place and so forth. The top three teams will be awarded a prize.

When registering, each team will be asked to pay a registration fee of $6.00 to enter the event.

Nanowrinkles, nanofolds yield strange hidden channels

Wrinkles and folds, common in nature, do something unusual at the nanoscale. Researchers at Brown University and in Korea have discovered that wrinkles on super-thin films have hidden long waves. The team also found that folds in the film produce nanochannels, like thousands of tiny subsurface pipes. The research could lead to advances in medicine,  electronics and energy. Results appear in Proceedings of the Royal Society A.

PROVIDENCE, R.I. [Brown University] — Wrinkles and folds are ubiquitous. They occur in furrowed brows, planetary topology, the surface of the human brain, even the bottom of a gecko’s foot. In many cases, they are nature’s ingenious way of packing more surface area into a limited space. Scientists, mimicking nature, have long sought to manipulate surfaces to create wrinkles and folds to make smaller, more flexible electronic devices, fluid-carrying nanochannels or even printable cell phones and computers.

A subsurface system of nanopipesResearchers at Brown University and in Korea used focusedion beams to extract a cross-section of compressed goldnanofilm. When tips of regular, neighboring folds touched,nanopipes were created beneath the surface.Credit: Kim Lab/Brown University

But to attain those technology-bending feats, scientists must fully understand the profile and performance of wrinkles and folds at the nanoscale, dimensions 1/50,000th the thickness of a human hair. In a series of observations and experiments, engineers at Brown University and in Korea have discovered unusual properties in wrinkles and folds at the nanoscale. The researchers report that wrinkles created on super-thin films have hidden long waves that lengthen even when the film is compressed. The team also discovered that when folds are formed in such films, closed nanochannels appear below the surface, like thousands of super-tiny pipes.

“Wrinkles are everywhere in science,” said Kyung-Suk Kim, professor of engineering at Brown and corresponding author of the paper published in the journal Proceedings of the Royal Society A. “But they hold certain secrets. With this study, we have found mathematically how the wrinkle spacings of a thin sheet are determined on a largely deformed soft substrate and how the wrinkles evolve into regular folds.”

Wrinkles are made when a thin stiff sheet is buckled on a soft foundation or in a soft surrounding. They are precursors of regular folds: When the sheet is compressed enough, the wrinkles are so closely spaced that they form folds. The folds are interesting to manufacturers, because they can fit a large surface area of a sheet in a finite space.

Kim and his team laid gold nanogranular film sheets ranging from 20 to 80 nanometers thick on a rubbery substrate commonly used in the microelectronics industry. The researchers compressed the film, creating wrinkles and examined their properties. As in previous studies, they saw primary wrinkles with short periodicities, the distance between individual wrinkles’ peaks or valleys. But Kim and his colleagues discovered a second type of wrinkle, with a much longer periodicity than the primary wrinkles — like a hidden long wave. As the researchers compressed the gold nanogranular film, the primary wrinkles’ periodicity decreased, as expected. But the periodicity between the hidden long waves, which the group labeled secondary wrinkles, lengthened.

“We thought that was strange,” Kim said.

It got even stranger when the group formed folds in the gold nanogranular sheets. On the surface, everything appeared normal. The folds were created as the peaks of neighboring wrinkles got so close that they touched. But the research team calculated that those folds, if elongated, did not match the length of the film before it had been compressed. A piece of the original film surface was not accounted for, “as if it had been buried,” Kim said.

Indeed, it had been, as nano-size closed channels. Previous researchers, using atomic force microscopy that scans the film’s surface, had been unable to see the buried channels. Kim's group turned to focused ion beams to extract a cross-section of the film. There, below the surface, were rows of closed channels, about 50 to a few 100 nanometers in diameter. “They were hidden,” Kim said. “We were the first ones to cut (the film) and see that there are channels underneath.”

The enclosed nano channels are important because they could be used to funnel liquids, from drugs on patches to treat diseases or infections, to clean water and energy harvesting, like a microscopic hydraulic pump.

Contributing authors include Jeong-Yun Sun and Kyu Hwan Oh from Seoul National University; Myoung-Woon Moon from the Korea Institute of Science and Technology; and Shuman Xia, a researcher at Brown and now at the Georgia Institute of Technology. The National Science Foundation, the Korea Institute of Science and Technology, the Ministry of Knowledge Economy of Korea, and the Ministry of Education, Science, and Technology of Korea supported the research.

Qunyang Li ScM ’07 PhD ’08 and Jin Qian ScM ’09 PhD ’10 Recognized by Chinese Government

Dr. Qunyang Li and Dr. Jin Qian, who received their Ph.D. degrees in Engineering (Solid Mechanics) in 2008 and 2010, respectively, from Brown University have been selected among 143 Young Scholars (younger than 40 in Science and Engineering) of 2011 by the Chinese government. Their selection is part of the "Thousand Young Talents Program" of the Chinese government, in which only 25 engineers were selected from all areas of engineering. The program was created by the Chinese government and aims to attract the best global young researchers to work in China. According to the program, each selected awardee will be awarded 500,000 RMB of living subsidies and up to 3,000,000 RMB for scientific research funding.

Qunyang Li

Li also received his master’s degree (2007, Applied Math) from Brown University and had been a post doctoral fellow at the University of Pennsylvania since 2008 until he was appointed as an associate professor at Tsinghua University this summer. Li received his bachelor’s degree and a master’s degree from Tsinghua University. During his time at Brown, Li won numerous awards, including the prestigious William N. Findlay Award in 2006 and the Outstanding Thesis Award in 2008.

Jin Qian

Qian had been a post doctoral fellow at Georgia Institute of Technology since September 2009 until he was appointed as an associate professor at Zhejiang University a month ago. Qian received his bachelor’s degree from Beijing University and a master’s degree from Institute of Mechanics of Chinese Academy of Sciences in addition to a master’s degree from Brown (Applied Math).