Abstract: A WLAN distributed/opportunistic scheduling (WDOS) method for acquiring a multi-user diversity gain is disclosed. The WDOS method allows a transmitter (i.e., a transmission user) to observe channel conditions of receivers (i.e., reception users), and commands the transmitter to transmit packets to a specific receiver having a relative good channel condition. The WDOS method uses a modified RTS/CTS exchange method to perform the channel probing. If the transmitter broadcasts the BRTS frame, each receiver transmits a CTS frame after the lapse of its backoff period. According to the reception signal strength distribution, the backoff delay time minimizes the number of CTS collisions irrespective of the number of receivers, reduces an amount of channel probing overheads, and maximizes a multi-user diversity gain. The better the relative channel condition, the lower the backoff delay time.
Type:
Grant
Filed:
September 13, 2006
Date of Patent:
September 7, 2010
Assignee:
Seoul National University Foundation
Inventors:
Seong-il Hahm, Jong-won Lee, Chong-kwon Kim
Abstract: A new SONOS memory device is provided, in which a conventional planar surface of multi-dielectric layers (ONO layers) is instead formed with a curved surface such as a cylindrical shape, and included is a method for fabricating the same. A radius of curvature of the upper surface of a blocking oxide can be designed to be larger than that of the lower surface of a tunneling oxide, which restrains electrons from passing through the blocking oxide by back-tunneling on erasing. As a result, a SONOS memory device shows an improvement in erasing speed.
Type:
Grant
Filed:
June 15, 2006
Date of Patent:
July 14, 2009
Assignees:
Seoul National University Foundation, Samsung Electronics Co., Ltd.
Abstract: A novel coordination complex formed by dinuclear metal complexation is provided. The complex is a dinuclear metal complex of a compound, wherein the compound comprises a conjugation ring system substituted with: a) an electron donating group selected from —OH, —SH and —NH2; b) an indicating group selected from a chromogenic group, a fluorescent group and an electrochemical group; and c) two binding auxiliary groups, in combination with the electron donating group each of which being coordinated with the metal to provide an anion bonding site, wherein as the complex binds to a anion, the coordination of the electron donating group with the metal is weakened and electron donation of the electron donating group to the conjugation ring system is reinforced such that the reinforced electron donation by the electron donating group is transferred through the conjugation ring system to the indicating group to produce an indicating signal concomitant with the change of its electronic density.
Type:
Grant
Filed:
May 27, 2004
Date of Patent:
October 9, 2007
Assignee:
Seoul National University Foundation
Inventors:
Jong-In Hong, Dong Hoon Lee, Ja Hyun Im, Seung Uk Son, Young Keun Chung
Abstract: An apparatus for generating and measuring bending vibration in a pipe buried underground or a pipe covered by insulating materials is disclosed. There is provided an apparatus for generating and measuring bending vibration in a non-ferromagnetic pipe without physical contact, comprising: a ferromagnetic strip adhered on a surface of the pipe; a coil wound around the surface of the pipe; two magnets for generating bias magnetic field, applied to the strip and parallel to the strip; a power source for supplying an electric current to the coil; and a measuring unit for measuring variation of voltage across the coil, the variation of the voltage being generated due to a strain according to inverse magnetostrictive effect, the strain being generated due to bending vibration, the bending vibration being generated due to deformation of the strip, the deformation being induced according to magnetostrictive effect as the power source supplies the electric current to the coil.
Type:
Grant
Filed:
December 3, 2004
Date of Patent:
November 28, 2006
Assignee:
Seoul National University Foundation
Inventors:
Yoon Young Kim, Soon Woo Han, Chan Park, II