Abstract: The present invention relates to the stabilization of an effective ingredient by using a mineral material. In the present invention, the effective ingredient can be stably supported using the mineral material, and a microcapsule obtained by the manufacturing method according to the present invention, when discharged to nature, causes no environmental problems due to encapsulation ingredients thereof being the same as soil ingredients, and thus can avoid micro-plastic issues.

Abstract: A random number generation method and apparatus are disclosed. In the random number generation method, a random number is generated using a plurality of digital signals existing in various storage devices, and thus the speed at which a random number is generated may be significantly increased.

Abstract: A data storage device protecting security code stored therein and a data storage system including same are disclosed. The data storage device efficiently prevents unauthorized access to the security code by allowing command descriptor block (CDB) information to be read using only a read-only memory (ROM).

Abstract: A method of detecting a free fall of a device includes measuring an acceleration of the device, calculating an integral of the acceleration, and determining whether the acceleration is periodic. If the acceleration is not periodic, the integral of the acceleration is compared with a first critical value to determine whether the device falls freely. If the acceleration is periodic, the integral of the acceleration is compared with a second critical value to determine whether the device falls freely. The first and second critical values are different. Since whether the device is periodically accelerated is considered, free fall of the device can be correctly detected, and thus malfunction of the device can be prevented. For example, an unnecessary protection operation for a hard disk drive of the device can be prevented, and thus a user can conveniently use the device.

Abstract: A data storage device protecting security code stored therein and a data storage system including same are disclosed. The data storage device efficiently prevents unauthorized access to the security code by allowing command descriptor block (CDB) information to be read using only a read-only memory (ROM).

Abstract: In a data storage device, unauthorized access to stored data in the data storage device can be effectively prevented by encrypting and storing security data needed for data encryption, setting an encryption key to encrypt/decrypt the security data by a user, and receiving the encryption key from a host, if necessary, not storing the encryption key in the data storage device.

Abstract: A random number generation method and apparatus are disclosed. In the random number generation method, a random number is generated using a plurality of digital signals existing in various storage devices, and thus the speed at which a random number is generated may be significantly increased.

Abstract: A method and system are disclosed for compensating disturbance applied to a plant, such as a HDD component, controlled by a state control device having an estimator & controller. The estimator & controller is adapted to generate a first control signal in response to a state signal indicating an estimated state of the plant. A second control signal is generated by applying a transfer function H(s) having defined gain/frequency characteristics to a control signal derived from the first control signal. An overall control signal is generated in response to the second control signal and the control signal derived from the first control signal and applied to the plant.

Abstract: A method of detecting a free fall of a device includes measuring an acceleration of the device, calculating an integral of the acceleration, and determining whether the acceleration is periodic. If the acceleration is not periodic, the integral of the acceleration is compared with a first critical value to determine whether the device falls freely. If the acceleration is periodic, the integral of the acceleration is compared with a second critical value to determine whether the device falls freely. The first and second critical values are different. Since whether the device is periodically accelerated is considered, free fall of the device can be correctly detected, and thus malfunction of the device can be prevented. For example, an unnecessary protection operation for a hard disk drive of the device can be prevented, and thus a user can conveniently use the device.

Abstract: In a hard disk drive (HDD), biases are measured across all zones of a disk, and nonlinear bias components are extracted. Upon a change in operational condition of the HDD, biases are measured at two reference positions on the disk so as to estimate a corresponding change in a linear bias component across all zones of the disk. The bias at a given position of the disk is then calculated based on the estimated linear bias component and the extracted nonlinear bias component.

Abstract: A data input/output control method and apparatus in an input/output subsystem are provided. The data input/output control method, in a system for inputting/outputting data to/from a disk sector according to an input/output command provided from a disk driver, includes: extracting the input/output commands for inputting/outputting the data to/from disk sector from the disk driver and generating a set of input/output commands; analyzing the load feature of the input/output command based on the set of input/output commands; determining whether the load of the input/output command corresponds to a multimedia application; and controlling the data which is input/output to/from the disk to correspond to the multimedia application according to the determination result.

Abstract: A speed control method of controlling a stepping motor to have a uniform instantaneous speed and an apparatus suitable for the same are provided. The stepping motor speed control method includes: calculating a repeated speed error for each phase while rotating a stepping motor at a constant speed and storing the calculated repeated speed error phase by phase; measuring a rotation speed of the stepping motor; sequentially and repeatedly reading the stored repeated speed errors phase by phase by synchronizing with the rotation of the stepping motor; and controlling the speed of the stepping motor with reference to the target speed, the measured speed and the repeated speed error for each phase. Accordingly, the stepping motor speed control apparatus rotates a stepping motor at a uniform instantaneous speed by controlling a rotation speed of the stepping motor phase by phase.

Abstract: A servo control method of controlling a plant to track a reference trajectory with enhanced accuracy using a reference signal and its derivative signals, an apparatus and a recording medium suitable for same. The servo control method includes: determining a polynomial indicating a reference trajectory desired by a plant and derivatives of the polynomial; sampling a plant output with respect to a plant input; generating a reference signal and its derivative signals with reference to a time between samples (a relative time); and determining a plant input at a sampling time using the generated reference signal and its derivative signals, a delayed plant input and a delayed plant output. Accordingly, a plant is controlled to track a reference trajectory with enhanced accuracy using a reference signal and its derivative signals.

Abstract: A method for writing a spiral reference servo signal suitable for a self-servo writing method in a hard disk drive includes writing a first reference pattern in an end direction of a spiral reference servo signal writing concentrically on the disk; writing a spiral reference servo signal on a current spiral track from a reference writing start position of the current spiral track; detecting a moving angle of a head to the first reference pattern, which corresponds to a distance from the reference writing start position to a reference writing end position of the spiral reference servo signal in the case that thermal expansion of the disk does not exist; compensating for a driving speed of the head with reference to the detected moving angle of the head; and writing the spiral reference servo signal on a next spiral track at a compensated driving speed of the head.

Abstract: An apparatus and method are provided for quickly and finely compensating for non-repeatable run out (NPRO) of a disc drive. The NPRO compensation control apparatus in a run out compensation apparatus of a system includes: a frequency estimator directly estimating a trigonometric function value of an NRRO frequency from a predetermined signal responding to the system using a correlation between a filter coefficient of a notch filter and a notch frequency; and an NRRO compensator canceling NRRO of the system using the trigonometric function value of the NRRO frequency estimated by the frequency estimator.

Abstract: A servo control device for a disk drive capable of effectively compensating for a low frequency disturbance incoming to the disk drive is provided. The servo control device includes: a state variable estimator calculating a position estimation error based on a control input for controlling motion of a head and a position error signal by using a predetermined state equation; an estimation filter calculating a disturbance estimation value from the position estimation error by using a mathematical relation between a disturbance and the position estimation error; and a subtractor subtracting the disturbance estimation value from the control input.

Abstract: A method and apparatus for navigating an unmanned vehicle using sensor fusion are provided. This method includes: measuring a plurality of parameters using at least two sensors that sense a result of a position estimation of the unmanned vehicle; selectively combining the measured parameters; detecting changes of the parameters within expected ranges; and estimating a position of the unmanned vehicle represented by an unknown state of sensor data and a desired inference, using estimation and error distribution. The apparatus is scalable, so it can be easily expanded or compressed under any environmental conditions. The apparatus is also survivable, so if a sensor source is lost or malfunctions, it is not a disaster for the whole system, but it just decreases exponential-related error estimation. The apparatus is also modular, so the apparatus can easily determine what kind of sensor is responsible for what kind of sensing.

Abstract: A settling control method and apparatus perform an improved settling control regardless of a seek distance when a disc drive track seek control operation is performed. An adaptive settling control method used in controlling the track seek mode of the disc drive includes: controlling a head to converge into a target position and a target velocity along with an eigen vector by transiting an initial state of the head motion onto an eigen vector line of a system at the time transiting from an acceleration/deceleration control mode of the track seek mode to a settling control mode.

Abstract: In a hard disk drive (HDD), biases are measured across all zones of a disk, and nonlinear bias components are extracted. Upon a change in operational condition of the HDD, biases are measured at two reference positions on the disk so as to estimate a corresponding change in a linear bias component across all zones of the disk. The bias at a given position of the disk is then calculated based on the estimated linear bias component and the extracted nonlinear bias component.

Abstract: A method, an apparatus and a computer readable recording medium storing a program for correctly detecting a free fall by referring to an acceleration and an integration of the acceleration. The method includes sensing an acceleration of the mobile device; integrating the sensed acceleration with respect to time; and determining the free fall by comparing the result of the integrating with a predetermined area threshold.