Patents Assigned to The Hong Kong University of Science & Technology
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Patent number: 6169852Abstract: The invention relates to an electrically-energized device for the rapid generation of steam or other vapors. The high-speed steam generator includes a wicked evaporator, a liquid reservoir, a liquid supply pipe, and a vapor transport tube. The evaporator consists of a low-thermal-conductivity porous wick, heated from a downward-facing grooved heating block that is in intimate contact with the upper surface of the wick structure. The grooved heating block is made of a copper block in which electric cartridge heaters are installed. As a heat load is applied on the heating block, an extremely steep temperature gradient is established immediately at the upper surface of the wick so that water from the saturated wick evaporates rapidly adjacent to the heated surface. Subsequently, menisci are formed at the vapor/liquid interface to develop a capillary force to pump subcooled liquid into the wick from the liquid reservoir.Type: GrantFiled: April 20, 1999Date of Patent: January 2, 2001Assignee: The Hong Kong University of Science & TechnologyInventors: Qiang Liao, Tianshou Zhao, Ping Cheng
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Patent number: 6146848Abstract: The present invention provides endonuclease-protected vegI promoters, constructs comprising same, bacteria transformed with same, expression products of said constructs produced by bacteria transformed with same, and methods of manufacturing said expression products using said transformed bacteria. Also provided are E. coli transformed with constructs having the vegI promoter, expression products of same and methods of manufacture of said expression products using said transformed E. coli.Type: GrantFiled: July 23, 1998Date of Patent: November 14, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Wan Keung Wong, Kat Hon Lam
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Patent number: 6091477Abstract: A liquid crystal display is described in which the need for a conventional output polarizer is eliminated and the display comprises only a liquid crystal cell, a single input polarizer, a reflector placed behind the cell, and a retardation film placed between the reflector and the cell. A Jones matrix simulation approach is used in order to obtain the parameters corresponding to solution spaces for the above design and several combinations are disclosed that give good results.Type: GrantFiled: March 25, 1997Date of Patent: July 18, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Hoi Sing Kwok, Shu Tuen Tang
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Patent number: 6081337Abstract: The present invention relates to methods and apparatus for measuring the optical properties, eg twist angle, cell gap, input director, of a transmissive or reflective liquid crystal cell. For a transmissive liquid crystal cell the cell is placed between a polarizer and an analyzer and the transmission spectrum observed while rotating the analyzer until zero transmission is obtained at at least one wavelength. The twist angle and the surface rubbing orientations of the liquid crystal cell are determined by the relative angle between the polarizer and the analyzer while the cell gap is determined from the calculated retardation value d.DELTA.n with known .DELTA.n. For reflective cells cell gap is determined based on a knowledge of twist angle and is accomplished by observing zero reflection wavelengths from a reflective cell with the polarizer and analyzer in cross-orientation.Type: GrantFiled: May 5, 1998Date of Patent: June 27, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Hoi-Sing Kwok, Shu-Tuen Tang
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Patent number: 6066272Abstract: Optical glasses and polymers are described that incorporate homogeneously dispersed fullerene molecules. The resultant materials may be used as optical filters, the cut-off frequency being easily adjustable by changing the fullerene content. To prepare glasses fullerene molecules are firstly functionalized by amination prior to being incorporated into a sol-gel process to prepare the glass. To prepare polymers a pre-existing polymer may be subject to fullerenation, or fullerene may be copolymerized with a selected monomer.Type: GrantFiled: October 7, 1996Date of Patent: May 23, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Ben-zhong Tang, Nai-teng Yu, Han Peng, Shuk-mei Leung, Xuan-zheng Wu
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Patent number: 6063867Abstract: The present invention provides a method for creating durable blends of polystyrene and polyolefin. The blends of the present invention have improved mechanical properties evidenced by measurement of impact strength, tensile strength, and elongation at break. Polyolefin is first crosslinked by creating a melt of polyolefin and a small amount of peroxide in a mixer at elevated temperature. The crosslinked polyolefin is then melt-blended with polystyrene at elevated temperature. Finally, a styrene-butadiene-styrene block copolymer is mixed into the melt. The method of the present invention can be applied to various blend systems of otherwise incompatible polymers provided it contains at least one component and a compatibilizer that are crosslinkable.Type: GrantFiled: February 12, 1998Date of Patent: May 16, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Zhi Wang, Chi-Ming Chan, Jiarui Shen
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Patent number: 6047000Abstract: A packet scheduling system is disclosed in which a plurality of first-in-first-out input buffers are provided each corresponding to a respective input data stream to a switching node or multiplexer. Credit is allocated to each stream having packets waiting to be transmitted and which is unable to transmit, and the next stream to be transmitted is based on the allocated credit values, the credit of a transmitted stream being reduced after transmission of a data packet from that stream.Type: GrantFiled: July 24, 1997Date of Patent: April 4, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: Danny Hin-Kwok Tsang, Brahim Bensaou, King Tung Chan
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Patent number: 6026177Abstract: A character recognition system is described, in particular a system suitable for use in monitoring cargo container codes or vehicle number plates. An image of the code is first analyzed to extract potential characters. As part of this process, long horizontal and vertical line segments are filtered out. The extracted potential characters are then input to a two-level character recognition means. The first level comprises a neural network classifier that classifies a character into a smaller set of possible characters; and then the second level comprises another neural network classifier which identifies which character among the smaller set of possible characters the extracted character is.Type: GrantFiled: August 29, 1995Date of Patent: February 15, 2000Assignee: The Hong Kong University of Science & TechnologyInventors: John Lee Chung Mong, Wong Wing Kin
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Patent number: 5982081Abstract: Field emitter structures are described for use in arrays forming field emission displays. The field emitter structures may be either single or perferably double-gate structures. To enhance the field emission current density the emitters are formed so as to be elongate so as to form a race-track shape. The emitter layer may also be provided with sharply defined edges in order to improve electron emission.Type: GrantFiled: December 6, 1996Date of Patent: November 9, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Johnny Kin On Sin, Bao Ping Wang
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Patent number: 5960032Abstract: High-rate bit transmitted data is serial to parallel converted into low-rate bit streams in a similar fashion to multicarrier or multitone modulation. However, in contrast to the multicarrier method, each low-rate bit stream is modulated using direct-sequence spread-spectrum. By selecting the processing gain properly the total required bandwidth will be of the same order as the original high-rate data stream, thereby gaining the inherent benefit of multipath rejection without expanding the bandwidth of the original high-rate stream.Type: GrantFiled: September 20, 1995Date of Patent: September 28, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Khaled Ben Letaief, Justin C-I Chuang, Ross D. Murch
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Patent number: 5942838Abstract: There is described a rotary motor in which a rotor disc is driven by a plate-like driving member comprising a laminate of piezoelectric material sandwiched between outer layers of anisotropic material. When a voltage is applied to the rotor disc the driving member expands into driving contact with the rotor disc and--at the same time--owing to the anisotropy of the outer layers, twists with a torsional movement and this torsional movement imparts a rotary movement to the rotor disc.Type: GrantFiled: August 19, 1997Date of Patent: August 24, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Shi Wei Ricky Lee, Hing Leung Li
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Patent number: 5937013Abstract: A receiver for down-converting a modulated carrier into its in-phase (I) and quadrature (Q) components for further processing is proposed. This is accomplished using a sampling method in which the signal is sampled directly using a sampling circuit which is driven by a single sampling clock frequency substantially lower than the carrier frequency while allowing the I and Q components to be precisely obtained. Each of the signal samples comprises sub-samples taken successively which represent the in-phase, quadrature, negative in-phase and negative quadrature components of the signal. The negative components permit flexible application of the invention in several modes, including differential mode for the removal of common-mode noise. The invention is useful because it provides an integrated circuit means for precisely obtaining I and Q components of a very high frequency modulated carrier.Type: GrantFiled: January 3, 1997Date of Patent: August 10, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Marcos Chun-Wing Lam, Curtis Chih-Shan Ling
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Patent number: 5926245Abstract: The invention provides a reflective liquid crystal display which consists of just an input polarizer, the liquid crystal cell and a rear reflector which can be placed inside or outside of the liquid crystal cell. There is no rear polarizer and no retardation film compensation. The invention is capable of producing a high contrast, low chromatic dispersion display. Depending on the twist angle chosen for the liquid crystal cell, the display can be used in direct view or in a projection type display. The display can also be driven in an active matrix mode or in a passive matrix multiplexed drive mode. A full numerical simulation which takes into account the liquid crystal director deformation under the application of an electric field was used to optimize such displays.Type: GrantFiled: March 25, 1997Date of Patent: July 20, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Hoi Sing Kwok, Fei Hong Yu
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Patent number: 5869847Abstract: A thin film transistor (TFT) comprises a n.sup.+ source region and a p.sup.+ drain separated by an undoped offset region, or the complementary structure with a p.sup.+ source and a n.sup.+ drain. By means of this arrangement in the offset region is conduction is by way of both electron and hole carriers and the offset region is conductivity modulated. The TFT of the present invention has lower on-resistance than a conventional thin film transistor.Type: GrantFiled: October 28, 1997Date of Patent: February 9, 1999Assignee: The Hong Kong University of Science & TechnologyInventors: Johnny Kin-On Sin, Anish Kumar Kottarath Parambil, Man Wong
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Patent number: 5853684Abstract: The present invention provides novel catalysts for the simultaneous removal of SO.sub.2 and NO.sub.x from flue gases. The catalysts may be supported or unsupported, pretreated or untreated, but allow the simultaneous reduction of SO.sub.2 to S and NO.sub.x to N.sub.2. Elemental sulfur is a useful byproduct of the process.Type: GrantFiled: August 21, 1997Date of Patent: December 29, 1998Assignee: The Hong Kong University of Science & TechnologyInventors: Ming Fang, Jian-Xin Ma
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Patent number: 5825023Abstract: An auto-focus laser incremental encoder for measuring linear or rotary motion or position of an object is described. An optical read head focuses three laser beams on the surface of a scaling grating. The grating is a reflection type grating where the height difference between adjacent pixels is one quarter of the wavelength of the laser light whereby the pitch of the grating can be detected by interferometric reflection. There are two sections of grating displaced with respect to each other so that a direction of movement can be readily determined. The third beam acts to provide an autofocus and is reflected from a smooth part of the grating between the two sections of reflective grating.Type: GrantFiled: March 26, 1997Date of Patent: October 20, 1998Assignee: The Hong Kong University of Science & TechnologyInventors: Lilong Cai, Jihua Zhang
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Patent number: 5804153Abstract: The present invention discloses a method for the catalytic reduction of sulfur dioxide, for example in flue gas, by carbon monoxide using lanthanum oxysulfide as the active catalyst. The catalyst is prepared from lanthanum oxide by hydration and sulfidization, the latter step being carried out in the gas stream itself. This method of preparation has more general applicability and can also be used as a method for the preparation of lanthanum, yttrium, gadolinium and lutetium oxysulfides generally.Type: GrantFiled: July 2, 1996Date of Patent: September 8, 1998Assignee: The Hong Kong University Of Science & TechnologyInventors: Ming Fang, Jian Xin Ma, Ngai Ting Lau
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Patent number: 5795554Abstract: The present invention discloses a method for the catalytic reduction of sulfur dioxide, for example in flue gas, by carbon monoxide using lanthanum oxysulfide as the active catalyst. The catalyst is prepared from lanthanum oxide by hydration and sulfidization, the latter step being carried out in the gas stream itself. This method of preparation has more general applicability and can also be used as a method for the preparation of lanthanum, yttrium, gadolinium and lutetium oxysulfides generally.Type: GrantFiled: January 29, 1997Date of Patent: August 18, 1998Assignee: The Hong Kong University of Science & TechnologyInventors: Ming Fang, Jian Xin Ma, Ngai Ting Lau
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Patent number: 5764190Abstract: A planar inverted-F antenna is described that is provided with a capacitive load that allows the dimensions of the antenna to be reduced from a conventional .lambda./4 to .lambda./8. To maintain good bandwidth and impedance matching in spite of the presence of the capacitive load, a capacitive feed is also provided.Type: GrantFiled: July 15, 1996Date of Patent: June 9, 1998Assignee: The Hong Kong University of Science & TechnologyInventors: Ross David Murch, Corbett Ray Rowell
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Patent number: 5757491Abstract: A laser interferometer system in particular for measuring the straightness of an object is described. This interferometer employs triangular prisms to refract the laser beams by certain angles with respect to the principal axis of the incident beam. Two configurations are described. One is for high accuracy in short range measurements, the other can handle long range measurements with high resolution that is not related to the range. For the latter the interferometer comprises a laser source, a beam splitter, a plane reflector, two first triangular prisms, a second prism, a right angle prism reflector and a detector system. The second prism and the right-angle prism reflector are integrated into one body to form a movable component and are attached to the object to be measured.Type: GrantFiled: August 19, 1996Date of Patent: May 26, 1998Assignee: The Hong Kong University of Science & TechnologyInventors: Lilong Cai, Jihua Zhang