Abstract: A method of correcting an output value of a geomagnetic sensor that recursively calculates a state estimate, an estimate gain vector, and an estimate error co-variance based on the output value of the geomagnetic sensor that is acquired sequentially and corrects the output value of the geomagnetic sensor based on the value includes acquiring a kth output value of the geomagnetic sensor, calculating a kth estimate gain vector based on a k?1th estimate error co-variance and the kth output value, calculating a kth state estimate based on the calculated kth estimate gain vector and the kth output value and a k?1th state estimate, calculating the kth estimate error co-variance using the kth estimate gain vector and a k?1th estimate error co-variance, and correcting the output value of the geomagnetic sensor based on the kth state estimate, wherein k is a natural number larger than 1.

Abstract: A method for calculating an angle of inclination of a magnetic field in a sensor coordination system includes measuring a magnetic field vector using a magnetometer, measuring an acceleration vector using an accelerometer, determining whether the sensor coordination system is in a moving state or a stationary state using the acceleration vector, and calculating the inclination angle of the magnetic field using the magnetic field vector and the acceleration vector, in response to the determining indicating the stationary state.

Abstract: A method of correcting an output value of a geomagnetic sensor that recursively calculates a state estimate, an estimate gain vector, and an estimate error co-variance based on the output value of the geomagnetic sensor that is acquired sequentially and corrects the output value of the geomagnetic sensor based on the value includes acquiring a kth output value of the geomagnetic sensor, calculating a kth estimate gain vector based on a k?1th estimate error co-variance and the kth output value, calculating a kth state estimate based on the calculated kth estimate gain vector and the kth output value and a k?1th state estimate, calculating the kth estimate error co-variance using the kth estimate gain vector and a k?1th estimate error co-variance, and correcting the output value of the geomagnetic sensor based on the kth state estimate, wherein k is a natural number larger than 1.

Abstract: A device and method for controlling synchronization in a device including receiving, from an access requesting program, a request for accessing a phonebook object stored in a terminal; determining whether the phonebook object is permitted to interoperate with the access requesting program; and providing information of the phonebook object if the phonebook object is determined to be permitted to interoperate with the access requesting program.