research
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Professor Sejin Kwon develops thruster for small satellite
- World’s first application of high-performance liquid propellant to small satellite thruster
- Show about four times higher thrust performance than the cold gas thruster of University of Surrey, the state-of-the-art technology in the field of small satellite
- Expect a considerable contribution to the extension of the lifespan and mission range of small satellites
The team of Professor Sejin Kwon (Department of Aerospace Engineering in KAIST/ President Nam Pyo Suh) and Space Solution Inc. (President Jaehun Lee) have jointly developed a micro thruster for small satellite motion-control.
Kwon"s team has succeeded in developing an integrated thruster which can be mounted on a satellite by integrating catalyst reactor and propellant-supplying system, which are the core technologies of small satellite thruster system.
For the first time in the world, Kwon’s team employs a high-performance liquid propellant to the thruster.
In the thruster, liquid-state hydrogen peroxide is dissolved into vapor and oxygen at the catalytic layer to emit a huge amount of heat. And, the emitted heat is converted into the kinetic energy of the gas to produce a propulsive force.
This thruster can perform the motion-control of a several tens-kilogram satellite with a propulsive force of less than one Newton and shows about four times higher thrust performance than the cold gas thruster of University of Surrey, who possesses the state-of-the-art technologies in the field of small satellites.
Professor Kwon said, “Although University of Surrey has also tried to develop a similar system, it’s not yet solved the problem on catalytic reactor bed. I expect this thruster will considerably contribute to the extension of the lifespan and mission range of scientific small satellites. Also, this thruster can be employed for the attitude control of the upper end of the launch vehicle, which is now being developed by the Korean Aerospace Research Institute (KARI).”
<Thruster module for small satellite application>
2006.09.05 View 13973 -
Korean Researchers Develop Skin-Like Tactile Sensor
THE KOREA TIMES2005.1.31(Mon)
A South Korean scientific research center said Sunday that it has developed a tactile sensor capable of functioning like human skin.
The left picture shows the letters of the Korea Advanced Institute of Science and Technology (KAIST) caught through a tactile sensor functioning like human skin and the right picture is its enlarged image. Scientists from KAIST developed the precision tactile sensor with 1-millimeter spatial resolution.
The tactile sensor is made of polydimethylsiloxane, a synthetic rubber, and has a 1-millimeter spatial resolution capability, the Korea Advanced Institute of Science & Technology (KAIST) said.
``Many tactile sensors have been developed so far, but ours has the highest spatial resolution capability, flexibility, softness and extensibility,’’ said Lee Hyung-kyu, who led the development project.
Late last year, the University of Tokyo unveiled a tactile sensor with a spatial resolution capability of 2 millimeters.
Lee said his team will announce the results of their research at an international conference on micro-electro-mechanical systems, to be held early next month in the U.S. city of Miami.
The new sensor is widely expected to lay the foundation for coating humanoids such as South Korea"s HUBO or Japan"s ASIMO with artificial skin.
HUBO is a humanoid robot recently developed by KAIST. It is capable of moving its fingers independently, dancing and shaking hands with people by using its 41 joints.
Japan"s ASIMO, an acronym for Advanced Step in Innovative Mobility, was unveiled in 2000 as the world"s most advanced bi-pedal robot.
Through several upgrades, it is now able to spin in the air, bend or twist its torso and maneuver around obstacles in its path.
2005.02.02 View 13861
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Nerve-protecting gene discovered
Korean scientists for the first time have identified a gene that blocks nerve damage from fevers and the use of narcotics, a state-run research institute said yesterday.
The finding may open the way for new medicine that can prevent the loss of brain function which is frequently caused by excessive stimulation of nerves and abnormally high body temperature.
"The research is in an early stage. But this approach has the potential to develop genetics-based preventatives against brain-attacking diseases," said Kim Jae-seob, a bioscience professor of the Korea Advanced Institute of Science and Technology, who led the study.
The researchers named the gene Pyrexia, which means fever. Kim"s team extracted it from genetically engineered fruit flies using a genome-screening system. In laboratory tests, they found that the gene is activated to 39 degrees Celsius or higher.
The researchers enhanced Pyrexia"s functionality in some fruit flies while removing the gene from others to observe their different reactions when exposed to high temperature.
"The fruit flies without the gene showed severe nerve disorder and suffered paralysis of brain function, while Pyrexia-enhanced flies maintained their normal brain conditions," the professor said.
The researchers got the same result from experiments with human cells, he said.
There are a lot of channel proteins, which enable ions to enter and exit the cell, that react to the level of temperature, but Pyrexia is the first of its kind that actually protects the neurons from external stimulus, he said.
The finding will appear on the March edition of the London-based science magazine Nature Genetics.
THE KOREA HERALD 2005.1.31 (thkim@heraldm.com) By Kim Tong-hyung
2005.02.02 View 13810
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Gene Protecting Brain Nerves Discovered
THE KOREA TIMES 2005.1.31By Kim Tae-gyu / Staff Reporter
South Korean scientists have for the first time discovered genes tasked with protecting brain nerves.
Korea Advanced Institute of Science and Technology professor Kim Jae-seob said Sunday the new genes, named pyrexia, shield brain nerves from outside stimuli, including high temperatures.
``The channel gene of pyrexia will open the door to developing new-concept medicines for brain damage in patients of high fever or drug addicts,’’ he said.
The channel gene refers to transport proteins, which provide a static passageway for a variety of essential substances to enter into cells.
``Up until now, a lot of channel genes activated by temperatures have been identified. But among them, pyrexia is first that guards brain nerves from external stresses,’’ Kim said.
Kim’s team learned pyrexia plays a pivotal role in the body through experiments with genetically engineered flies that did not have any pyrexia.
Up to 60 percent of the pyrexia-depleted mutants were paralyzed within three minutes of exposure to a temperature of 40 degrees Celsius.
In comparison, just 9 percent of normal flies were paralyzed with the same stimulus, indicating pyrexia is responsible for protecting animals from high-temperature stress.
``Our next goal is to develop pyrexia-embedded drugs, which can be expected to commercially debut in about five years,’’ Kim said.
Kim has already applied for international patents for his medical breakthrough, which will be printed in the March edition of Nature Genetics, a science journal.
voc200@koreatimes.co.kr
2005.02.02 View 13950
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KAIST Develops Thinking, Feeling Human-Like Robot
By Kim Tae-gyu / Staff ReporterTHE KOREA TIMES 2005.1.31(page 1)
South Korean scientists created the world"s first artificial species, a software robot with ``genes"" and ``chromosomes.""
Kim Jong-hwan, professor at Korea Advanced Institute of Science and Technology, said Sunday his team had developed a robot with 14 chromosomes, which gives the machine a ``personality.""
``This robot is a software-based one, sometimes called a sobot. It has a unique synthetic character determined by its specific combination of 14 chromosomes,"" the 47-year-old Kim said.
When Kim"s team gave a stimulus to the chromosome-equipped sobots, they showed totally different responses even under the same environment due to their distinctive personalities.
Several cognitive sensors enable the prototype models to identify 47 differing outside stimuli. The virtual robots also have 77 behavior patterns.
``Because a sobot is basically a software system, it can easily travel to other robots and multiply. In the middle of such processes, it can evolve through crossover and mutation,"" Kim said.
With the development of associated technologies, Kim expected the number of chromosomes would be augmented as sobots evolve to a more sophisticated species in the future.
The capacity to load large volumes of data is related to the evolution of sobots. Currently, 14 chromosomes consist of roughly 2,000 bytes of data.
The effort to incorporate the sobot into a platform, robot hardware, is now underway and Kim"s team looks to unveil the new-concept species as soon as next month.
``Diverse behavior patterns driven by sobots" specific personalities will be precisely translated into action just like the soul rules the body,"" Kim said.
Kim did not think the robotic evolution would lead to the human race being threatened; the concept of the recent blockbuster ``I, Robot.""
``If we design the chromosomes safely, the self-reproducing robot will not post a threat back to us,"" Kim said.
Kim first revealed the robotic breakthrough at a keynote speech of the International Conference on Autonomous Robots and Agents, held in New Zealand last December.
Kim is also known as pioneer in the field of robot football and has headed the Federation of International Robot-soccer Association (FIRA) since its foundation in 1999.
voc200@koreatimes.co.kr
2005.02.02 View 14847
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Researchers Find Mechanism of Tumor Suppressor Genes
By Kim Tae-gyu. Staff ReporterTHE Korea Times 02-06-2004
Korean scientists continue to break new ground in fighting cancer as domestic researchers examined the mechanism of a gene which can help detect and treat various sorts of cancer.
Korea Advanced Institute of Science and Technology (KAIST) Prof. Lim Dae-sik on Thursday said his team uncovered the mechanism of RASSF1A (Ras Association Domain Family 1 A), or tumor suppressor genes, for the first time in the world.
The gene was widely considered to play an important role in reducing the proliferation of cancer cells, but its exact function and processes have remained unknown up to now.
It is the second cancer-related breakthrough by Koreans in a week after Korea Institute of Science and Technology (KIST) Prof. Chung Hesson unveiled the oral anti-cancer drug.
``Cancer results from the failed management of cell cycles due to things like radiation. After a two-year intensive study, we found out how RASSF1A governs the cell cycle,"" Lim said.
Lim added cancer is caused by abnormal cells, which continue to grow and divide out of control unlike normal cells, which die over time. Cancer cells develop into malignant tumors, eventually inflicting damaging effect on the human body.
As a result, a lack of the RASSF1A indicates a high possibility of cancer and injection of it into cells is believed to help cure the deadly disease, according to Lim.
Dr. Song Min-sup, who took charge of the research, said the findings will especially pave the way for the detection and treatment of lung cancer.
``The dearth of RASSF1A was reported mostly in the case of lung cancer. The new findings will provide insight into the diagnosis and cure of lung cancer from its early stages,"" Song explained.
Lung cancer is a very elusive disease because it doesn"t cause symptoms in its infancy. When symptoms do occur, usually it is too late.
``We expect commercial detection kits or drugs for lung cancer in around five years after pre-clinic experimentation and two-phase clinic trials,"" Song expected.
Details of the study is available in the scientific journal Nature Cell Biology in its February edition.
voc200@koreatimes.co.kr
2004.03.15 View 16381
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Personal data found on many used hard drives
JoongAng Daily2004.3.9
Many secondhand computer hard drives that are being sold through the Internet formerly belonged to businesses and are therefore full of business records containing personal information, the Korea Advanced Institute of Science and Technology (KAIST), a leading local science and technology school, said yesterday.
To determine whether personal information had been properly deleted, the business database research team at KAIST"s business school conducted an experiment in which it randomly bought 41 hard drives through Internet auction sites beginning in April 2003 and analyzed their contents.
It said 26 hard drives out of the total, or 65 percent, had not even been reformatted to remove data. On those drives were business records containing the names, birth dates, home and company addresses, telephone numbers and health examination records of 1,349 people. Also, the team found 568 resident identification numbers on the drives.
"Secondhand hard disks are an open storehouse of personal information [from business records]," said the team"s head, Moon Young-chul. "We found such personal data for an average of 60 people per used disk."
Mr. Moon said that reformatting hard drives alone will not delete all information recorded on them. He said special software designed to completely delete data should be used or such disks should be destroyed.
2004.03.15 View 12136