Abstract: A semiconductor memory device includes a source layer, a channel structure, gate electrodes on the source layer and spaced apart on a sidewall of the channel structure, and a common source line. The gate electrodes include a first word line group including first and second gate electrodes and a second word line group including third and fourth gate electrodes. The semiconductor memory device, in response to a voltage of the common source line reaching a target voltage, causes an inhibition voltage to be applied to the second word line group and an erase voltage to be applied to the first word line group in a first erase operation interval, and causes the inhibition voltage to be applied to the first word line group and the erase voltage to be applied to the second word line group in a second erase operation interval.

Abstract: The present invention relates to a portable X-ray tube, and more particularly, to a portable X-ray tube capable of miniaturization and weight reduction by reducing the structural volume of the X-ray tube by installing cathodes in the same direction together with the fixed anode. The portable X-ray tube comprises: an anode portion comprising an anode heat sink for conducting and dissipating heat transferred through the anode, an anode formed on the upper part of the anode heat sink, and an anode target formed on the inclined surface of the upper end of the anode; a cathode portion installed in parallel with the anode through the installation hole of the cathode portion formed in the anode heat sink; and a vacuum bulb fixed to the heat sink to seal the anode portion and the cathode portion with a vacuum; wherein the X-rays emitted through the anode target are irradiated to the upward direction as the installation direction of the anode.

Abstract: The present invention relates to a solar evacuated heat collecting panel for collecting solar energy and more particularly, to a solar evacuated heat collecting panel having a heat absorbing plate and a heat medium circulating tube mounted therein so as to withstand external stress by means of a glass window structure and to minimize loss of solar energy collected therein.

Abstract: Provided is a vacuum solar thermal collector module including a case having an open top and an internal space, a vacuum thermal collector panel provided inside the case and having a vacuum inside, and an insulation disposed between the vacuum thermal collector panel and the case to block heat transfer, wherein the vacuum thermal collector panel is plural and arranged in a horizontal direction inside the case.

Abstract: The present invention relates to an X-ray tube with non-evaporable getters disposed therein for maintaining a degree of vacuum sufficient to operate the X-ray tube. The present invention provides a fixed-anode X-ray tube and a rotating-anode X-ray tube in which non-evaporable getters are disposed. The X-ray tubes, even when rated power is introduced without an aging process, can perform gas adsorption sufficiently and stably during operation, despite gases that can be generated by the filament and the cathode focusing cap and gases that can be generated by the target.

Abstract: Provided is a vacuum solar thermal collector module including a case having an open top and an internal space, a vacuum thermal collector panel provided inside the case and having a vacuum inside, and an insulation disposed between the vacuum thermal collector panel and the case to block heat transfer, wherein the vacuum thermal collector panel is plural and arranged in a horizontal direction inside the case.

Abstract: The present invention relates to a vacuum insulation panel to be used as an insulation material, which panel has an improved structure to improve insulation properties over conventional vacuum insulation panels filed with fillers within outer plates. The present panel includes a spacer within vacuumed space, thereby supporting the structure of outer plate against atmospheric pressure and minimizing conductive thermal transfer.

Abstract: The present invention relates to a vacuum insulation panel to be used as an insulation material, which panel has an improved structure to improve insulation properties over conventional vacuum insulation panels filed with fillers within outer plates. The present panel includes a spacer within vacuumed space, thereby supporting the structure of outer plate against atmospheric pressure and minimizing conductive thermal transfer.

Abstract: The present invention relates to an X-ray tube with non-evaporable getters disposed therein for maintaining a degree of vacuum sufficient to operate the X-ray tube. The present invention provides a fixed-anode X-ray tube and a rotating-anode X-ray tube in which non-evaporable getters are disposed. The X-ray tubes, even when rated power is introduced without an aging process, can perform gas adsorption sufficiently and stably during operation, despite gases that can be generated by the filament and the cathode focusing cap and gases that can be generated by the target.