Abstract: A power converter for operating with an alternate current power source, including a storage capacitive means and a transformer, said storage capacitive means being adapted for power factor correction, said transformer including an input for connecting to an alternating current power source and at least a first output and a second output respectively for connecting to said storage capacitive means and the load, said transformer including input windings, first output windings and second output windings which are respectively connected to said input, said first and second outputs wherein said transformer and said storage capacitive means being adapted that the voltage across said storage capacitive means being related to the voltage of said first output of said transformer.
Abstract: A woven fabric consists of a generally uniformly woven structure of hydrophobic and hydrophilic materials and has inner and outer exposed surfaces of hydrophobic and hydrophilic materials. The inner exposed surface is between 40% and 70% hydrophobic material, and the outer exposed surface is predominantly hydrophilic material.
Abstract: Low-frequency duct noise is relatively difficult to deli with by passive methods such as porous duct lining. Reactive methods like expansion chamber are rather bulky, while compact resonators are too narrow-banded. This invention shows that a suitably stretched thin membrane backed by a slender cavity can achieve a satisfactory performance from low to medium frequencies over an octave band.
Abstract: An internal torque balancing method of short fiber yarns related to the art of textile and the manufacturing apparatus thereof. The present invention proposes a completely new mechanical processing method of single torque-free yarns, and applies it into the process of ring spinning. Said method accomplishes a machine and a possibility of processing single torque-free yarns within one processing step by simple improvement on the existing ring spinning machine. Said technique is applicable to the production of all types of short fiber materials, and can overcome the maximum bundle yarn count of Ne limit of the torque-free yarns processed by the existing physical balancing technique. Meanwhile, said technique can process the yarns with low twist, which is unable to be processed normally by the conventional ring spinning machine. The torque-free singles ring spinning machine has good mechanical behavior, good handle, and evenness without residual torque.
Abstract: A system and method for the three-dimensional analysis and reconstruction of the surface of a thin flexible material has a sample holder for supporting the flexible material over a curvature and a camera for capturing profile images of the surface at the curvature. The images are transferred to a computer which is programmed to extract profile height information from the images and produce three-dimensional data representing the surface of the flexible material. The profile height information is extracted by applying a histogram analysis to the images, applying a threshold, and extracting height information.
Abstract: A DC to DC converter includes a switch, a diode, and a capacitor connected in series with an inductor. The capacitor and inductor provide a resonant time period and are connected in series with the switch and the diode. A control circuit provides an on/off signal to the switch and has a switching time period longer than half the resonant time period.
Abstract: Digital communication schemes using chaotic signals as carriers can be broadly classified into two categories. In the first category, the chaotic signals carrying the information have to be synchronously regenerated at the receiver, which may be applicable to low noise environment. The second category requires no synchronous regeneration of the carrying chaotic signals in the receiver. An example of the second category utilizes a specific bit structure, which may not be able to resist unintended reception because the fabricated bit structure can be relatively easily detected. This invention involves systems and methods for transmitting digital messages modulated as chaotic signals, and the demodulation methods. One individual chaotic signal generator having a specific chaotic characteristic value is responsible for generating a chaotic signal for each possible value of the digital message according to a chaotic algorithm.
Abstract: A method of three dimensional measurement, evaluation, and grading system for fabric/textile structure/garment appearance, based an values P and Q, is carried out using a fixed digital camera positioned above a piece of the fabric, shining at least two different parallel light beams from inclined directions onto the surface of the fabric and capturing different reflected images of the surface with the camera. The captured images are analysed to derive certain parameters relevant to the appearance. In particular, values of P+Q may be used in a grading evaluation, where P and Q are summations of the surface gradients for a plurality of evenly distributed points in an x direction and in a y direction of the surface, respectively.
Abstract: Enantiomeric resolution is realized by combining an electrochemical method with ligand exchange (LE) in a novel electrochemical method named chiral ligand exchange potentiometry. Chiral selector ligands preferentially recognize certain enantiomers and undergo ligand exchange with the enantiomeric labile coordination complexes to form diastereoisomeric complexes. These complexes can form in solution and be recognized by an unmodified electrode, or they can be immobilized on the surface of a modified electrode (chiral sensor) incorporated with the chiral selector ligand by polysiloxane monolayer immobilization (PMI). Considerable stereoselectivity occurs in the formation of these diastereoisomeric complexes, and their net charges (Nernst factors) are different, thus enabling enantiomers to be distinguished by potentiometric electrodes without any pre-separation processes.
Abstract: A compact moiré effect body scanner provides 3-D images of a human body for use in making up suitable garments. The scanner includes an elongate projection module with a photographic grid that illuminates the body. An elongate imaging module having a second photographic grid lies alongside the projection module and a digital camera is used to capture images of the body. The scanner is typically about 400 mm long, 400 mm high, and 150 mm wide and can be used in normal room light conditions.
Type:
Grant
Filed:
October 10, 2000
Date of Patent:
November 2, 2004
Assignee:
The Hong Kong Polytechnic University
Inventors:
Wing Man Yu, Keng Po Ng, Man Chi Yan, Hong Bo Gu
Abstract: A circuit board comprising a dielectric material provided with a conductive layer is drilled with laser operated at an energy density below the ablation threshold of the conductive layer. The method of drilling includes providing on the conductive layer an ablation layer having an ablation threshold near or below that laser energy density, directing the laser at a target area of the ablation layer to ablate portions of the conductive and dielectric layers in the target area, and removing any remaining ablation layer from the conductive layer.
Abstract: A composite textile fabric includes a composite layer of a hydrophobic material and a layer of a hydrophilic material knitted or otherwise formed together. The composite layer has an upper surface of small exposed areas of the hydrophilic material covering a total area about 25% of the overall area of the upper surface. The composite layer provides one way liquid transport for moisture, extending from the upper surface towards a lower surface of the composite layer.
Type:
Grant
Filed:
January 16, 2001
Date of Patent:
October 19, 2004
Assignee:
The Hong Kong Polytechnic University
Inventors:
Yi Li, Kwok Wing Yeung, Yi Lin Kwok, Weilin Xu
Abstract: A method of controlling the state of polarization of an optical signal includes injecting the optical signal into a laser diode and matching the wavelength of the optical signal to a longitudinal mode of the laser diode. A stabilizer signal can also be injected in to the laser diode. The wavelength of the stabilizer signal is matched a first longitudinal mode of the laser diode a longitudinal mode of the laser diode to the optical signal.
Type:
Application
Filed:
March 17, 2003
Publication date:
September 23, 2004
Applicant:
The Hong Kong Polytechnic University
Inventors:
Ping-kong Alexander Wai, Hwa Yaw Tam, Lai Yin Simon Chan, Weng Hong Chung
Abstract: An audio trigger device has a number of buttons that can be depressed to create different audio signals with 5 different features. The audio signals are used to remotely control a computer running slide presentation software that has an audio channel to collect sound signals. The features of the audio signals are detected by the computer as commands for controlling the progress of the slide presentation by simulating keystrokes, mouse actions, or their combinations for the control commands of the presentation software.
Abstract: An apparatus for grinding an organic material into a power includes a first grinding member with a first grinding surface and a second grinding member with a second grinding surface. The first and second grinding members are rotatably positioned adjacent each other for grinding an organic material between the fist and second grinding surfaces. The first and second grinding surfaces include a plurality of radii defining a plurality of sectors. The sectors are provided with rows of teeth parallel to a respective radius.
Abstract: A DC to DC converter includes a switch, a diode and a capacitor in series with an inductor. The capacitor and inductor provide a resonant time period and are connected in series with the switch and the diode. A control circuit provides an on/off signal to the switch and has a switching time period of longer than half the resonant time period.
Abstract: A process for chemically bonding an oxide matrix to a textile surface, comprises providing a dry textile substrate, coating the substrate with a nanosol preparation, and curing the coated substrate.
Type:
Application
Filed:
December 19, 2002
Publication date:
June 24, 2004
Applicant:
The Hong Kong Polytechnic University
Inventors:
John Haozhong Xin, Walid Abdelhamid Daoud, Xiao Ming Tao
Abstract: Open end yarn is passed through a drawing zone located between a front roller and a back roller controlled to rotate at different velocities. An air jet nozzle is located between the two rollers and directs a jet of air at the yarn. The drawing improves various characteristics of the yarn, making the processed yarn more suitable for making textile articles.
Abstract: A system for analyzing fabric surface appearance includes a feed mechanism for running a fabric over a crest including a frame for holding the fabric bent to form a crest, an image capturing device for capturing profile images of the fabric surface at the crest, and a computer system for manipulating the images. The computer system produces a three-dimensional representation of the fabric surface and identifies characteristics in the three-dimensional representation. The information is compared to reference data to identify a grade for the fabric.
Type:
Grant
Filed:
June 6, 2002
Date of Patent:
April 27, 2004
Assignee:
The Hong Kong Polytechnic University
Inventors:
Jinlian Hu, Binjie Xin, Yueyang Guo, Edward Newton
Abstract: A circuit board is made from a polymer material and includes a predetermined portion which has magnetic or dielectric or resistive properties. The portion with the magnetic or dielectric or resistive properties is made first and arranging within a mold. A polymer is then applied to the mold to form a board incorporating the portion with the magnetic or dielectric or resistive properties.