Abstract: A scrubber system may include a scrubber housing including a vertically extended cleaning space, an inflow chamber coupled to a bottom portion of the scrubber housing, and first and second inflow portions, each of which is configured to supply a gas into the inflow chamber. The inflow chamber may include a mixing space, and the mixing space may be connected to the cleaning space. The first inflow portion may include a first connection pipe coupled to the inflow chamber to provide a first connection path and the second inflow portion may include a second connection pipe coupled to the inflow chamber to provide a second connection path. The first and second connection paths may be extended toward the mixing space in opposite directions, respectively, and may be connected to opposite portions of the mixing space, respectively.

Abstract: The present invention relates to a method and apparatus of radio link selection based on delay spread, the user equipment according to the present invention receives radio signals from neighboring multiple base stations, measures delay spread of the signals received from the multiple neighboring base stations, selects at least one base station among the neighboring base stations based on the delay spread measured, and connects a radio link with the selected at least one base station. According to the present invention, the inter-symbol interference due to delay spread can be decreased, thereby it is available to implement the maximum transmission speed in a given propagation environment.

Abstract: A method of providing millimeter wave band-based communication connection service, includes measuring a strength of a signal received from at least one base station that forms at least one cell; and storing signal data based on the measured strength of the signal so that the signal data is mapped to the at least one base station. Further, the method includes selecting any one base station from among the at least one base station based on the stored signal data; and connecting communication to the selected base station. Further, the method is performed on a millimeter wave band-based mobile communication terminal.

Abstract: A ray path tracing method using a three-dimensional (3D) modeling structure, includes: generating and developing a 3D modeling structure of a glass window and a window frame; setting a ray transmitting point and a ray receiving point at respective positions, and generating a ray from the transmitting point; and forming a path of a transmitted wave ray, passing through the glass window and analyzing a propagation characteristic of the transmitted wave ray. Further, the ray path tracing method includes forming respective paths of the transmitted wave ray, a reflected wave ray, and a diffracted wave ray, and analyzing respective propagation characteristics of the transmitted wave ray, reflected wave ray, and diffracted wave ray; and calculating electric field intensities at the receiving point about all the paths formed between the transmitting point and the receiving point.

Abstract: An apparatus for inspecting, measuring, or inspecting and measuring a reflective photomask may comprise a light illuminating part including a light source and beam shaping part; a stage configured to cause the light generated to be incident at an angle through the beam shaping part; and/or a light detector configured to receive optical image information of the photomask mounted on the stage. An apparatus for inspecting, measuring, or inspecting and measuring a reflective photomask may comprise a light illuminating part including a light source and configured to adjust a progress direction of light from the light source at an angle; a stage in a direction at which the light is irradiated from the light illuminating part at the angle and configured to mount the photomask; a slit plate between the light illuminating part and the stage; and/or a light detector configured to receive image information of the photomask.

Abstract: Disclosed is an apparatus and method for ray-tracing using a path preprocess. The method for ray-tracing including launching a ray from a transmitting point at angles with regular intervals, setting a first side of an object where the launched ray is projected as a reference patch, and searching predetermined preprocessed path data for a counterpart patch corresponding to a second side of another object, the second side being exposed to the projected ray reflected or diffracted from the set reference patch, and tracing a transmission path of the reflected or diffracted ray.

Abstract: A method of forming a photomask using a calibration pattern that may exactly transfer a desired pattern to a substrate. The method includes providing one-dimensional calibration design patterns each having first design measures and providing two-dimensional calibration design patterns each having second design measures; obtaining one-dimensional calibration measured patterns using the one-dimensional calibration design patterns and obtaining two-dimensional calibration measured patterns using the two-dimensional calibration design patterns; obtaining first measured measures of the one-dimensional calibration measured patterns and obtaining second measured measures of the two-dimensional calibration measured patterns; establishing a correlation between the first measured measures and the second measured measures; and converting a main measured measure of a main pattern into a corresponding one of the first measured measures using the correlation.

Abstract: A method and apparatus for modeling radio propagation is provided. In the method, when a wall having a thickness is modeled as a line having no thickness, an error in a shade area is minimized by considering the thickness of a wall while maintaining simplicity in a ray-tracing method.

Abstract: Provided is an apparatus and method for downsizing surface elevation data. The method includes receiving surface elevation data consisting of a plurality of cells, sequentially searching all the cells in a predetermined direction, comparing data of a cell having a predetermined reference elevation value or more with data of nearby cells, setting the cell as a boundary region when there is a nearby cell having different elevation data than the cell, grouping cells having the same data centered on the cell set as the boundary region, and performing triangulation on the basis of the grouping results. Since pieces of the same elevation data among pieces of high-resolution surface elevation data used in an outdoor environment are grouped as one, it is possible to carry out efficient analysis and improve analysis speed.

Abstract: A method for 3D preprocessing for ray tracing includes: selecting and storing visible surfaces by designating one of a plurality of structures as a reference structure and remaining structures as relative structures, searching for the relative structures from the reference structure, storing relative structures having a surface visible from the reference structure, and removing relative structures having an invisible surface; conducting selection and storage based on distance measurement by measuring the distance from the reference structure to each of the stored relative structures and removing relative structures positioned beyond a reference spot predetermined with reference to the reference structure; and calculating a ray propagation path by calculating the propagation path of the ray between the reference structure and each of the relative structures stored in said conducting selection and storage based on distance measurement.

Abstract: Disclosed is a calibration method using a vector network analyzer including: acquiring impulse responses for a direct wave and a multi-reflected wave generated by transmitting and receiving devices connected to a measuring port of the vector network analyzer; setting a gate only for an impulse response for the direct wave among the impulse responses for the acquired direct wave and multi-reflected wave; and transforming the impulse response for the direct wave to which the gate is set into a frequency domain signal and defining the transformed frequency domain signal as calibration results.

Abstract: A method of forming a photomask using a calibration pattern that may exactly transfer a desired pattern to a substrate. The method includes providing one-dimensional calibration design patterns each having first design measures and providing two-dimensional calibration design patterns each having second design measures; obtaining one-dimensional calibration measured patterns using the one-dimensional calibration design patterns and obtaining two-dimensional calibration measured patterns using the two-dimensional calibration design patterns; obtaining first measured measures of the one-dimensional calibration measured patterns and obtaining second measured measures of the two-dimensional calibration measured patterns; establishing a correlation between the first measured measures and the second measured measures; and converting a main measured measure of a main pattern into a corresponding one of the first measured measures using the correlation.

Abstract: An apparatus for analyzing radio wave propagation in a radio wave system includes: an identification unit configured to search and identify all objects existing in a service area in which users are provided with services; a construction unit configured to calculate a relative position between the identified objects and acquire a radio wave propagation model based on visibility at respective objects; and an analysis unit configured to apply the radio wave propagation model to ray tracing dynamically and analyze radio wave propagation in the service area.

Abstract: Disclosed is a three dimensional ray tracing method in a dynamic radio wave propagation environment. The method of tracing three dimensional ray in a dynamic radio wave propagation environment, by which cross tests are performed on a plurality of radio wave blocking obstacle surfaces according to a ray tube tracing scheme based on an image method in a simulation area, in which the plurality of radio wave blocking obstacle surfaces are modeled, to detect a radio path between a first point and a second point, the method comprising: defining at least a part of the radio wave blocking obstacle surfaces as valid radio wave blocking obstacle surfaces, the radio wave blocking obstacle surfaces being within a visible region from the first point of which location varies dynamically; and tracing a ray between the first point and the second point by taking into consideration only the defined valid radio wave blocking obstacle surfaces to be simulated.

Abstract: Provided is a millimeter waveband signal receiving device and method. The millimeter waveband signal receiving method includes receiving a plurality of millimeter waveband signals via a plurality of paths, selecting a switching path from among the plurality of paths based on the plurality of received millimeter waveband signals, and setting a communication connection to the selected switching path.

Abstract: A method for 3D preprocessing for ray tracing includes: selecting and storing visible surfaces by designating one of a plurality of structures as a reference structure and remaining structures as relative structures, searching for the relative structures from the reference structure, storing relative structures having a surface visible from the reference structure, and removing relative structures having an invisible surface; conducting selection and storage based on distance measurement by measuring the distance from the reference structure to each of the stored relative structures and removing relative structures positioned beyond a reference spot predetermined with reference to the reference structure; and calculating a ray propagation path by calculating the propagation path of the ray between the reference structure and each of the relative structures stored in said conducting selection and storage based on distance measurement.

Abstract: Disclosed is an apparatus and method for ray-tracing using a path preprocess. The method for ray-tracing including launching a ray from a transmitting point at angles with regular intervals, setting a first side of an object where the launched ray is projected as a reference patch, and searching predetermined preprocessed path data for a counterpart patch corresponding to a second side of another object, the second side being exposed to the projected ray reflected or diffracted from the set reference patch, and tracing a transmission path of the reflected or diffracted ray.

Abstract: A method and apparatus for modeling radio propagation is provided. In the method, when a wall having a thickness is modeled as a line having no thickness, an error in a shade area is minimized by considering the thickness of a wall while maintaining simplicity in a ray-tracing method.

Abstract: A apparatus for evaluating interference of a cognitive radio transmission signal with digital TV broadcasting includes a cognitive radio transmission unit generating and transmitting an interference signal using orthogonal frequency division multiple access (OFDMA), a broadcast transmission unit generating and transmitting a baseband digital TV broadcast signal containing data about a program to be broadcast, and a broadcast receiving evaluation unit evaluating a signal interference on the digital TV broadcast signal due to the interference signal from a signal combining a broadcast signal that the broadcast transmission unit transmits and the interference signal that the cognitive radio transmission unit transmits, by the signal interference.

Abstract: Provided are a transceiver and a transceiving method for use in an ultra wide band system for frequency sharing. The transceiver for use in an ultra wide band system for reducing interference that can be generated by an external system includes an external signal detector which detects an external signal generated from the external system, and a transmission signal controller which determines a power level of a transmission signal to be transmitted by the transceiver based on a power level of the detected external signal, in the case where an external signal using the same frequency channel as the ultra band system is detected, wherein the ultra wide band system and the external system are in a frequency sharing environment.