Abstract:
A backlight driving apparatus for a liquid crystal display device includes a light source, an AC driver for supplying a high voltage AC power to turn on the light source, and a protection circuit electrically connected to the AC driver responsive to an input voltage lower than a reference voltage for stopping the driving of the AC driver.
Abstract:
A backlight driving apparatus for a liquid crystal display device includes a light source, an AC driver for supplying a high voltage AC power to turn on the light source, and a protection circuit electrically connected to the AC driver responsive to an input voltage lower than a reference voltage for stopping the driving of the AC driver.
Abstract:
A funnel in a CRT includes a body part welded to a panel, a cone part connected to the body part having a deflection yoke fitted thereto, and a neck part connected to the cone part having an electron gun sealed therein. The cone part is formed such that &Dgr;Y/&Dgr;X={YD-(DD*sin&thgr;2)}/{XD-(DD*cos&thgr;2)} is greater than 4, where DD denotes a diagonal length, XD denotes a long axis length, YD denotes a short axis length, and &thgr;2 denotes a diagonal angle between the long axis and the short axis.
Abstract:
A laser verticality/horizon indicator for construction is provided that realizes irradiation of laser beam, and indication of both a vertical point and a horizontal line using optical refraction. The laser verticality/horizon indicator embodies a scientific and systematic use mechanism through electrically controlled operation of equipment to indicate vertical and horizontal positions as a precise measurement, and to enhance the handling efficiency of the equipment. The laser verticality/horizon indicator includes a mounting board having a driving motor, a rotary bulb, a prism mounted in the rotary bulb, a battery receiving bulb used as a power supply, and a laser inducing hole. The laser verticality/horizon indicator further includes a laser generator separately mounted on the mounting board, and a plumb bob forming a body structure of the verticality/horizon indicator, the mounting board and the laser generator being installed in the plumb bob.
Abstract:
The present invention provides a composite separator for a polymer electrolyte membrane fuel cell (PEMFC) and a method for manufacturing the same. The inventive method involves allowing graphite foil layers to be brought into direct contact with each other when graphite foils are stacked on both sides of a carbon fiber reinforced composite material prepreg, thereby improving electrical conductivity in the thickness direction of the separator.
Abstract:
The present invention provides a separating plate for a fuel cell stack and method of manufacturing the same, and more particularly, to a separating plate for a fuel cell stack and method of manufacturing the same, in which the separating plate constituting the fuel cell stack is formed in such a fashion as to interpose an array of metal pipes between two sheets of composite material, and a gasket abutting against the separating plate is formed in such a fashion as to define hydrogen and air flow channels, thereby removing a contact resistance between two adjoining separating plates constituting unit cells to improve the efficiency of the fuel cell.
Abstract:
There are provided a LED driving apparatus and a liquid crystal display apparatus using the same, in which a circuit configuration of the LED driving apparatus can be simplified and the cost of the LED driving apparatus can be saved in employing a LED as a light source of the liquid crystal display apparatus. The LED driving apparatus comprises a plurality of n LED lamps, constant voltage providing units that provide constant voltages to the plurality of LED lamps, respectively, a Pulse Width Modulation (PWM) control signal providing unit that provides PWM signals to the constant voltage providing units, respectively, and a feedback control unit that receives voltages feedbacked through the plurality of LED lamps, compensating for the voltages as constant voltages suitable for constant current driving of each of the LED lamps, and sequentially outputs the constant voltages to the constant voltage providing units, respectively, based on time-dividing.
Abstract:
A simple method of preparing a homogeneous cellulose solution is disclosed, which comprises the steps of (a) preparing fibrillar cellulose powder; (b) injecting a molten liquid tertiary amine oxide solvent into a twin screw extruder; (c) feeding the cellulose powder of step (a) into a section of the twin screw extruder where the molten liquid tertiary amine oxide solvent fed in step (b) produces a well swollen paste with the cellulose powder fed in step (c); (d) dissolving the well swollen cellulose paste in the following melting sections in the twin screw extruder; and (e) stabilizing the solution obtained in step (d) in a storage tank.
Abstract:
A first printed circuit board is disposed on a first side of the cover. A second printed circuit board is disposed on a second side of the cover. A first connector and a second connector are disposed on the first and second printed circuit boards, respectively. A through hole is formed in a region of the cover that corresponds to the first connector. The first and second connectors are electrically connected to each other through the through hole.
Abstract:
Provided is a laryngeal stroboscope using voice signals. The laryngeal stroboscope includes a photography unit for photographing a patient's vocal cords and a light source for illuminating a part to be photographed, a microphone for sensing the patient's voice, a high-pass filter for passing voice signals of 100 Hz or more among voice signals output from the microphone, a low-pass filter for removing signals of harmonic components from the voice signals output from the high-pass filter and passing only a voice signal in a fundamental frequency band, a peak detector for detecting a peak of the voice signal output from the low-pass filter and obtaining a pitch, and a controller for controlling the light source to intermittently emit light in response to a signal output from the peak detector and controlling the photography unit to operate according to whether or not the light is intermittently emitted.