Abstract:
A joint structure between a top nozzle and a guide thimble of a nuclear fuel assembly and, more particularly, a structure for joining an inner-extension tube, the top nozzle and the guide thimble. When an inner-extension tube head, which is provided as a means for facilitating removal of the top nozzle of the nuclear fuel assembly from the guide thimble, is removed from an inner-extension tube body to separate the top nozzle from the nuclear fuel assembly, the inner-extension tube body is prevented from undesirably rotating, so that the guide thimble and the inner-extension tube body can maintain the joined state.
Abstract:
Disclosed herein is a joint structure between a top nozzle and a guide thimble. The joint structure includes an outer guide post, an inner-extension tube head, an inner-extension tube body, a wedge and the guide thimble. The outer guide post is provided with an external thread formed on a lower end thereof. The inner-extension tube head includes an annular retaining part formed on an upper end thereof. An internal thread is formed on a medial portion of the inner-extension tube head. An external thread is formed on each of upper and lower ends of the inner-extension tube body. A stop protrusion is provided under a lower end of the wedge. The wedge is welded to the inner-extension tube body after the top nozzle has been joined with the guide thimble. A stop protrusion receiving depression is formed in the guide thimble.
Abstract:
Disclosed is a spacer grid assembly with mixing vanes supporting fuel rods of nuclear fuel assemblies and mixing coolant that flows around the fuel rods, and more particularly, a spacer grid equipped with mixing vanes that mix coolant flowing around fuel rods.The spacer grid with hydraulically balanced mixing vane patterns, in the spacer grid equipped with a strip dividing a plurality of unit grid cells and a plurality of springs, protruded in uniform directions of vertical and horizontal directions on a grid surface of the strip and supporting nuclear fuel rods, which includes: a plurality of mixing vanes protruded to the downstream of coolant on an upper end of the inner grid surface, wherein positions and directions of the mixing vanes are formed in regular patterns on the spacer grid. Thus, it can minimize coolant flow induced vibration of the spacer grid by balancing hydraulic load generated by the mixing vanes, around the center of the spacer grids.
Abstract:
A slot antenna is provided. The slot antenna includes a feeding unit of a strip line shape which is disposed on a first surface of a substrate, a ground which is disposed on a second surface of the substrate, and an antenna element which is formed by connecting two sub slots formed on the second surface of the substrate, wherein each of the sub slots is arranged at an edge of the ground in an internal direction of the ground. Accordingly, the size of the antenna is reduced, and more area is provided for arranging components of a terminal.
Abstract:
A joint structure between a top nozzle and a guide thimble of a nuclear fuel assembly and, more particularly, a structure for joining an inner-extension tube, the top nozzle and the guide thimble. When an inner-extension tube head, which is provided as a means for facilitating removal of the top nozzle of the nuclear fuel assembly from the guide thimble, is removed from an inner-extension tube body to separate the top nozzle from the nuclear fuel assembly, the inner-extension tube body is prevented from undesirably rotating, so that the guide thimble and the inner-extension tube body can maintain the joined state.
Abstract:
A Multi-Band antenna system includes an antenna which resonates in a plurality of frequency bands and a controller which drives the antenna. The antenna includes a ground plate and a plurality of radiators which are formed on both sides of the ground plate in directions perpendicular to a surface of the ground plate in a space at an edge of the ground plate, wherein each radiator is connected to the edge of the ground plate.
Abstract:
A method for quickly searching a cell at a mobile station by using a synchronization channel structure of a forward link in a code division multiple access system which operates by an asynchronous mode between base stations is provided. In the method, a predetermined starting point among a plurality of locations of sync channel codes in a frame with respect to a base station having a minimal channel loss is obtained. Long code group and frame sync information at the mobile station are obtained based on outputs of a matched filter every mini slot clock location for one frame time after a starting point of a current mini slot. A long code based on the obtained long code group and frame sync information obtained is detected wherein the long code is used for band-spreading of a forward link by a current base station.
Abstract:
A miniaturized multiple input multiple output (MIMO) antenna includes a first antenna element disposed in a first side of a substrate in a round form; a second antenna element in a round form symmetrically with the first antenna element and disposed in the first side of the substrate; and a ground disposed in a second side of the substrate. The first antenna element and the second antenna element are disposed such that electro magnetic waves resonating in the first antenna element and the second antenna element are orthogonally polarized. Accordingly, the antenna size can be reduced. The miniaturized antenna facilitates the component design in the small terminal.
Abstract:
The present invention relates to an anti-fretting wear spacer grid having a plurality of canoe-shaped springs formed thereon, wherein each of the canoe-shaped springs includes: a fuel rod-contacting part having a flat surface having a predetermined longitudinal length so as to have linear contact with the fuel rod; a curved face-connecting part formed on the upper and lower portions of the fuel rod-contacting part; a leg-connecting part formed on the end portion of the curved face-connecting part; and legs each being formed of a plate shape having a predetermined length and connecting the both sides of the leg-connecting part with one unit grid cell surface.
Abstract:
Disclosed herein is a joining structure between a top nozzle and guide thimbles in a nuclear fuel assembly, which can prevent a rotation of inner insertion tube bodies when the top nozzle is separated from the nuclear fuel assembly and promote convenience in assembling and disassembling the top nozzle and the guide thimbles.