Abstract:
An analog sampling apparatus for a liquid crystal display device includes: a data driver to generate an analog data voltage; a data output bus line to receive the analog data voltage; a first sampling and holding circuit connected to the data output bus line to compensate an offset voltage in the analog data voltage and to supply the analog data voltage to a data line of a liquid crystal display panel; and a second sampling and holding circuit connected to the data output bus line arranged to sample the analog data voltage while the analog data voltage is supplied to the data line by the first sampling and holding circuit. The first sampling and holding circuit is arranged to supply the analog data voltage while the second sampling and holding circuit samples the analog data voltage, and to sample the analog data voltage while the second sampling and holding circuit supplies the analog data voltage.
Abstract:
A liquid crystal display device includes first thin film transistor with a first polysilicon active layer in which a first channel area has first grain boundaries, wherein the first thin film transistor has a first channel direction different from a first grain boundary direction of the first grain boundaries, and a second thin film transistor with a second polysilicon active layer in which a second channel area has second grain boundaries, wherein the second thin film transistor has a second channel direction parallel to a second grain boundary direction of the second grain boundaries, wherein the first and second transistors have a substantially same electrical characteristic.
Abstract:
A quadrifilar helical antenna comprising two pairs of filars having unequal lengths and phase quadrature signals propagating thereon. A conductive H-shaped impedance matching element matches a source impedance to an antenna impedance. The impedance matching element having a feed terminal at the center thereof from which current is supplied to the two filars of each filar pair disposed about an edge of the impedance matching element and symmetric with respect to a center of the impedance matching element. The impedance matching element further comprises a reactive element for matching the antenna and source impedances.
Abstract:
A phase shifter which uses bragg gratings and having tunable phase shift functions with respect to input signals in an RF band without using a separate RF device. The phase shifter includes a dielectric layer, a first conductive layer formed on an upper surface of the dielectric layer lengthwise along the dielectric layer so as to provide a signal path for the input signal, a second conductive layer formed at a first end of a lower surface of the dielectric layer so as to form bragg gratings lengthwise along the dielectric layer, a third conductive layer formed at a second end of the lower surface of the dielectric layer in line with the second conductive layer so as to form bragg gratings lengthwise along the dielectric layer, and a moving unit for adjusting a distance between the second conductive layer and the third conductive layer within a predetermined length. The phase of the signal of the RF band is shifted by adjusting the distance between the second and third conductive layers without using a separate RF device, thereby significantly reducing the manufacturing cost for the phase shifter.
Abstract:
The present invention relates to an apparatus for fixing a roof rack to a vehicle roof. Particularly, the present invention relates to an apparatus for facilitating mounting and dismounting of a roof rack for loading various kinds of freight thereon by structurally improving a vehicle roof to employ a unified single roof molding. According to the present invention, there is provided an apparatus for fixing a roof rack to a vehicle roof of the type comprising a roof panel 100 in which roof molding engagement portions 110 are longitudinally formed to be depressed along both sides of the vehicle roof, and roof moldings 200 inserted into and engaged with the roof molding engagement portions 110 of the roof panel 100. Further, the apparatus of the present invention comprises engagement openings 210 formed to pass through the roof moldings, and movable covers 300 placed in the interiors of the roof moldings to allow the engagement openings 210 to be resiliently opened and closed. Therefore, since the unified single roof molding can be employed by structurally improving the vehicle roof, irrespective of whether or not the roof rack is used, the number of parts and the cost of production can be reduced and production processes can be simplified. Further, since the roof rack can be easily mounted to and dismounted from the roof modling, a user's convenience increases. Furthermore, since the interior of the roof molding cannot be seen when the roof rack has been dismounted from the roof molding, the aesthetic appearance of the vehicle roof can be enhanced.
Abstract:
A MoSi2—Si3N4 composite coating which is coated on a surface of base materials which are molybden, molybden alloy, molybden-coated niobium or molybden-coated niobium alloy and a manufacturing method thereof. The MoSi2—Si3N4 composite coating on the surface of the base material can be formed by forming a Mo2N diffusion layer by vapor-depositing of nitrogen on the surface of the base material and forming a MoSi2—Si3N4 composite coating by vapor-depositing of silicon on the surface of the Mo2N diffusion layer, or the MoSi2—Si3N4 composite coating on the surface of the base material can be formed by forming a MoSi2 diffusion layer by vapor-depositing of silicon on a surface of a base material by the CVD method, transforming the MoSi2 diffusion layer into a Mo5Si3 diffusion layer by heating under a high-purity hydrogen or argon atmosphere, forming a Mo2N—Si3N4 composite diffusion layer by vapor-depositing of nitrogen on the surface of the Mo5Si3 diffusion layer by the CVD method and forming a MoSi2—Si3N4 composite coating by vapor-depositing of silicon on the surface of the Mo2N—Si3N4 composite diffusion layer. The MoSi2—Si3N4 composite coating manufactured by the above method is characterized as a structure in which Si3N4 particles are distributed in a MoSi2 grain boundary of equiaxed grains, thus to improve cyclic oxidation resistance of the base material, improve low-temperature oxidation resistance, and improve mechanical properties of the coating. Therefore, transmission of fine cracks by the thermal stress can be restrained.