摘要:
An end-fed planar type spiral antenna for transmitting/receiving radio signals includes a spiral pattern formed to have inner and outer spiral curves turned predetermined times in a spiral shape from an arbitrary center point in a plane; a central circle pattern formed in a part of a central region of the spiral pattern in a circular shape; and a feed arm pattern formed in a rectangular shape from an end of the spiral pattern that turns predetermined times. Conductive material is patterned on a pattern where the spiral pattern, the central circle pattern and the feed arm pattern are overlapped. This antenna allows to design an antenna structure capable of effectively enhancing radiation efficiency and improving broadband characteristics by utilizing a tapered spiral structure. Also, this antenna has an improved orientation, ensures less limitation in height, and allows a small-size design.
摘要:
A variable valve lift apparatus may include an opening/closing portion, a low lift cam which selectively contacts the opening/closing portion, a high lift cam which may be disposed parallel to the low lift cam, a control portion, a pad hinge connected to the control portion, and a pad, an end of which may be pivotally coupled to the pad hinge, the pad slidably contacting the high lift cam and the opening/closing portion, wherein, the control portion selectively changes position of the pad hinge.
摘要:
The present invention relates to an apparatus and method for providing a bandwidth of a cognitive radio system. An apparatus and method for providing a bandwidth of a cognitive radio system according to an exemplary embodiment of the present invention calculates an oscillation frequency of a local signal that changes, by a predetermined value, center frequencies of fractional bands as bands that arc not used temporally and spatially in partial bands of an externally provided broadcasting channel band. The apparatus and method for providing a bandwidth of a cognitive radio system outputs a first local signal at the calculated oscillation frequency, mixes the output first local signal and an external signal, and moves center frequencies of fractional bands of the external signal by a predetermined value. The apparatus and method for providing a bandwidth of a cognitive radio system Filters a frequency band that is higher than an upper limit of a pass band having a predetermined bandwidth among moved frequency bands of the fractional bands to extract a first signal. Then, the apparatus and method for providing a bandwidth of a cognitive radio system mixes the extracted first signal and a second local signal and moves the center frequencies of the fractional bands in the first signal. The apparatus and method for providing a bandwidth of a cognitive radio system filters a frequency band that is lower than a lower limit of the pass band among the moved frequency bands of the fractional bands to extract at least one fractional band. The apparatus and method for providing a bandwidth of a cognitive radio system provides the extracted fractional band to a terminal and a base station, thereby improving frequency utilization efficiency.
摘要:
Erasure methods for a nonvolatile memory cell that includes a gate electrode on a substrate, source and drain regions in the substrate at respective sides of the gate electrode, and a charge storage layer interposed between the gate electrode and the substrate. A nonzero first voltage is applied to the source region starting at a first time. While continuing to apply the first nonzero voltage to the source region, a second voltage having an opposite polarity to the first voltage is applied to the gate electrode starting at a second time later than the first time. The second voltage may increase in magnitude, e.g., stepwise, linearly and/or along a curve, after the second time.
摘要:
Erasure methods are provided for a nonvolatile memory cell that includes a gate electrode on a substrate, source and drain regions in the substrate at respective sides of the gate electrode, and a charge storage layer interposed between the gate electrode and the substrate. A nonzero first voltage is applied to the source region starting at a first time. While continuing to apply the first nonzero voltage to the source region, a second voltage having an opposite polarity to the first voltage is applied to the gate electrode starting at a second time later than the first time. The second voltage may increase in magnitude, e.g., stepwise, linearly and/or along a curve, after the second time.
摘要:
A vibration-sound generating device and yoke thereof are described. The vibration-sound generating device comprises a diaphragm, a vibration part comprising a magnet and a yoke, which is positioned apart from the diaphragm by a desired distance, a suspension elastically supporting the vibration part, a supporting part supporting the diaphragm and the suspension, and a voice coil electromagnetically driving the diaphragm and the vibration part. The yoke of the invention has higher specific gravity and magnetic permeability than iron. So that it can improve performance of vibration and sound device.
摘要:
A compound of the following formula ##STR1## wherein m is an integer of 1 to 3, R.sub.1 and R.sub.2 are the same or different and each is hydrogen atom or lower alkyl, and R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are the same or different and each is hydroxy or a group of the formula ##STR2## (wherein n is 0 or 1, X is --NH-- or --O--, Y is alkylene, A is hydrogen atom, lower alkyl, lower alkoxy, halogen atom or trifluoromethyl, and B is alkyl or alkenyl), with the proviso that two or three of R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are hydroxyl groups and that when two of them are hydroxyl groups, the cases where R.sub.3 and R.sub.5 are hydroxy, and R.sub.4 and R.sub.6 are hydroxy are excluded; a complex compound comprising said compound and a metallic atom; and a diagnostic agent containing said complex compound. The above compound is useful as a chelating agent and the complex compound comprising said compound and a metallic atom exhibits superior characteristics as a contrast medium for image diagnosis.
摘要:
A method and apparatus for detecting a signal using a cyclo-stationary characteristic value is provided. A method of detecting a signal using a cyclo-stationary characteristic value includes: calculating cyclo-stationary characteristic values with respect to a cyclic frequency domain of an input signal; multiplying the calculated cyclo-stationary characteristic values with each other; and detecting the signal from the input signal based on the result of the multiplication.
摘要:
Provided is a method of sharing a data transceiver, a data transceiver antenna, a sensing receiver, and a sensing antenna, and a wireless communication system. The data transceiver and the sensing receiver, or the data transceiver antenna and the sensing antenna may be flexibly shared based on a condition. During a period where a transceiver and an antenna are utilized, the transceiver and the antenna may be utilized for different purposes. The transceiver and the antenna may be flexibly shared to increase efficiency in using the transceiver and the antenna, and thus, a spectrum sensing and a data transmission and reception performed in a system may be improved.