Abstract:
A system and a method for determining a satellite image loss and a computer-readable recording medium therefor are provided. The satellite image loss determination system includes a data receiving unit configured to receive packet data including satellite image data, time information, and a flag value, and angle data of a scan mirror that generates the satellite image data; a data comparing unit configured to compare the angle data received by the data receiving unit with angle data of the scan mirror previously determined in correspondence with the packet data; and an image loss determining unit configured to determine whether a loss has occurred in a satellite image generated from the satellite image data in consideration of a result of comparison of the data comparing unit.
Abstract:
An apparatus and method for containing and charging an unmanned VTOL aircraft are disclosed. The apparatus for containing and charging an unmanned VTOL aircraft includes a post, an extended member, a cover, a fastening unit, and a charging unit. The post is placed on a ground. The extended member is connected to the post. The cover is provided on the extended member, and is configured to be opened or closed in order to contain and protect the unmanned VTOL aircraft. The fastening unit is provided in the cover, and is configured to fasten the unmanned VTOL aircraft. The charging unit is provided in the fastening unit, and is configured to charge the unmanned VTOL aircraft.
Abstract:
Provided is an apparatus for controlling a driving speed of an antenna of a mobile satellite travelling in an orbit. The apparatus may include a calculator configured to calculate an azimuth position range and an elevation position range for an effective beam width of the antenna based on an antenna orientation at which the antenna of the mobile satellite is oriented correctly to a ground station from a point in the orbit, and a controller configured to control a speed of the antenna based on a first azimuth in the azimuth position range and a first elevation in the elevation position range.
Abstract:
Provided is an unmanned aerial vehicle that broadcasts a route and future location information of the unmanned aerial vehicle within preset coverage based on sensing data and current location information of the unmanned aerial vehicle. The unmanned aerial vehicle includes a calculator configured to calculate a predicted route and second location information of the unmanned aerial vehicle corresponding to a preset period of time based on first location information and sensing data; and a transmitter configured to periodically broadcast a first notification signal that includes the first location information, the predicted route, and the second location information.
Abstract:
A method of detecting an unknown signal and estimating a source location of the unknown signal using aircraft based on an automatic dependent surveillance-broadcast (ADS-B) system is provided. The method includes a first step (S100′) for obtaining from a plurality of airborne aircrafts provided with a network system, an aircraft signal transmitted to neighboring aircraft. The method further includes a second step (S200′) for detecting, by one of the plurality of aircraft, a presence of the unknown signal in the aircraft signal based on one of a time difference of arrival (TDOA) method, a time of arrival (TOA) method, and an angle of arrival (AOA) method. The method further includes a third step (S300′) for estimating the source location of the unknown signal and a fourth step (S400′) for transmitting unknown signal generation information and the source to neighboring aircraft and the ATC through a flight information services-broadcast (FIS-B).
Abstract:
A cryocooler, includes a cylinder filled with gas. A piston rectilinearly reciprocates inside of the cylinder and compresses or expands the gas. A connecting rod has a first side coupled to the piston and moves with the piston, and a second side having a first thread along an outer circumference thereof. A linear motor rectilinearly reciprocates a motor shaft toward the connecting rod in accordance with a control signal. A sleeve has two open sides, so that an end portion of the motor shaft can be supported by and inserted in one open side, and the second side of the connecting rod can be inserted in the other open side, and an inner circumference of the sleeve is formed with a second thread that engages with the first thread of the connecting rod and rotates to adjust a distance between the motor shaft and the connecting rod.
Abstract:
Provided is a sphere magnetic levitation system having magnetic-aligning devices that magnetically align the position of a sphere levitated by electromagnets according to whether the sphere is levitated, and a method of operating the sphere magnetic levitation system. The sphere magnetic levitation system includes: a sphere; a plurality of electromagnets symmetrically positioned about the sphere and spaced apart from the sphere at equal distances; and a plurality of magnetic-aligning devices provided around the sphere, and coming into contact with the sphere or separated from the sphere by a predetermined distance according to the modes of the system. The system is operated in one mode from among: an idle mode, in which the magnetic-aligning devices are in direct contact with and support the sphere; and an operation mode, in which the magnetic-aligning devices are separated from the sphere and the sphere is levitated and rotated.
Abstract:
Provided is an apparatus for measuring an input time of an input signal, and more particularly, an apparatus for measuring an input time of an input signal more precisely than a reference clock using a delay circuit.
Abstract:
Provided is a satellite navigation visibility calculation apparatus. The satellite navigation visibility calculation apparatus includes a processing unit configured to binarize an input sky view image to create an binary image, an extraction unit configured to extract a plurality of feature points from the binary image, and a calculation unit configured to calculate satellite navigation dilution of precision (DOP) corresponding to the sky view image using the plurality of feature points.
Abstract:
Provided is a method for estimating and calibrating an absolute misalignment between an attitude control sensor of a satellite or a flight vehicle imaging and transmitting ground images having high resolution and an imaging payload.