Abstract: A method of rotating a surveillance camera having an acceleration sensor and being controllable by a processor to maintain a tilt-angle to conform to a command tilt-angle, includes the steps of moving the surveillance camera tilt to a predetermined command tilt-angle in response to a signal from the processor; periodically calculating estimated tilt-angles by using acceleration values in at least one axis of an acceleration sensor; calculating a difference value between an estimated tilt-angle of a current period and an estimated tilt-angle of a previous period; and when the difference value between the estimated tilt-angles exceeds a set limit, moving the camera to another position to correct the tilt angle according to the difference calculate.

Abstract: A method of controlling panning of a surveillance camera configured to perform panning over a set angle during a preset mode includes: obtaining an edge value with respect to each pixel of an object captured image of a panning-completed time, the edge value being a difference between brightness of a left adjacent pixel thereof and brightness of a right adjacent pixel thereof; obtaining an object vertical-line number among vertical pixel lines of the object captured image, the object vertical-line number being a number of a vertical pixel line in which a sum of the edge values is largest; and correcting the panning such that the object vertical-line number coincides with a reference vertical-line number corresponding to the panning over the set angle.

Abstract: The present invention provides an aerial wind power generating system which has an improved structure such that despite light wind, satisfactory wind power generation can be ensured, and such that it is easy to install and remove the system, thus being effectively adapted to a temporary and portable wind power generating system. The system of the present invention includes a floating body (20), which is connected to support wires coupled to a wire rotating unit, a wind passage (30), which is formed through the floating body, so that wind passes through the wind passage in the horizontal direction, and a wind power generating unit (40), which has turbine blade assemblies and generators (48). The turbine blade assemblies are installed in the wind passage and are thus rotated by wind passing through the wind passage. The generators generate electric energy using rotating force transmitted from the turbine blade assemblies.

Abstract: The present invention provides an aerial wind power generating system which has an improved structure such that despite light wind, satisfactory wind power generation can be ensured, and such that it is easy to install and remove the system, thus being effectively adapted to a temporary and portable wind power generating system. The system of the present invention includes a floating body (20), which is connected to support wires coupled to a wire rotating unit, a wind passage (30), which is formed through the floating body, so that wind passes through the wind passage in the horizontal direction, and a wind power generating unit (40), which has turbine blade assemblies and generators (48). The turbine blade assemblies are installed in the wind passage and are thus rotated by wind passing through the wind passage. The generators generate electric energy using rotating force transmitted from the turbine blade assemblies.

Abstract: A lamp system including: a power-factor compensator, a current controller including first and second switches, the current controller being coupled to the on/off periods of the first and second switches for controlling the magnitude of a lamp driving current from the power-factor compensator; a lamp section including a resonance circuit composed of a resistor, an inductor and a capacitor, and emitting light under a current from the current controller; a ballast for forming a feedback voltage using a current flowing through the lamp section including soft start and dimming control. The lamp system compares the feedback voltage to a reference voltage to determine whether the current input to the lamp section is an overcurrent, an undercurrent, or a normal current. The ballast controls the on/off periods of the first and second switches.

Abstract: A lamp system including: a power-factor compensator, a current controller including first and second switches, the current controller being coupled to the on/off periods of the first and second switches for controlling the magnitude of a lamp driving current from the power-factor compensator; a lamp section including a resonance circuit composed of a resistor, an inductor and a capacitor, and emitting light under a current from the current controller; a ballast for forming a feedback voltage using a current flowing through the lamp section including soft start and dimming control. The lamp system compares the feedback voltage to a reference voltage to determine whether the current input to the lamp section is an overcurrent, an undercurrent, or a normal current. The ballast controls the on/off periods of the first and second switches.

Abstract: An electronic ballast for use in illuminating a lamp includes a lamp driving circuit having a pulse-width modulated signal generator, a timing capacitor coupled to the lamp driving circuit, and a power controller. The power controller uses a current sense resistor to detect a current flowing through the lamp and an operational amplifier circuit to compare a signal associated with the detected current to a reference voltage associated with a desired lamp current. Based on the comparison, the power controller provides a correction current to the timing capacitor to control a duty cycle of an output of the pulse-width modulated signal generator.

Abstract: Disclosed is an electric ballast system.

Abstract: A switching power supply having a high efficiency starting circuit uses a field effect transistor to provide initial starting current to a pulse width modulated signal generator within a switching control circuit. The field effect transistor (FET) has a drain connected to a source of supply voltage, a source connected to the PWM signal generator, and a gate connected to a feedback voltage that is derived from an output voltage of the switching power supply. During start up of the switching power supply, the FET provides current to the PWM signal generator. When the feedback voltage reaches a predetermined level, the FET supplies substantially near zero current to the PWM signal generator, thereby eliminating the electrical inefficiencies typically associated with a conventional switching power supply starting circuit.