Abstract: The present invention discloses a method of adjusting writing parameters, comprising the steps of testing a region to be written in a re-writeable optical disc without changing writing power level; calculating writing parameters in the region to be written based on the tested result; and adjusting writing parameters based on the calculated result. According to embodiments of the present invention, the direct over writing compatibility problem can be resolved. Moreover, power level adjusting is kept unchanged so as to avoid possible damage to direct over writing cycleability.

Abstract: Parallel inverters without any communication buses and the controlling method thereof are provided. The parallel inverters are controlled by an instant voltage. Each inverter includes an output voltage waveform controller and a load-sharing controller. The output voltage waveform controller is connected to an output terminal of the inverter to control the waveform of an output voltage of the inverter. The load-sharing controller is connected to the output voltage waveform controller to control the load-sharing of the inverter and to make each inverter have the same phase, active power and reactive power without communications.

Abstract: A test system for testing a network device is provided. The test system includes a control device and a cable group. The control device receives a user instruction, generates a test instruction according to the user instruction, and includes a control board and a relay board. The control board parses the test instruction, and generates a control signal. The relay board is connected to the control board, and comprises a plurality of switches, various of the switches are switched on or off according to the control signal. The cable group includes a plurality of cables with different lengths, the cables electrically connected to the switches, for forming a test line with a required length according to the control signal. A system and a method for automatically adjusting a length of a test line are also provided.

Abstract: The present invention provides a three-level ac generating circuit and the control method thereof. The three-level ac generating circuit includes a three-level boosting circuit connected to an input source and including a positive boosting portion and a negative boosting portion; and a three-level inverting circuit connected to the three-level boosting circuit and including a positive inverting portion and a negative inverting portion, wherein while the input source is a relative low voltage, the relatively low voltage is boosted via the three-level boosting circuit, inverted and output via the three-level inverting circuit; while the input source is a relatively high voltage, the relatively high voltage is inverted and output via the three-level inverting circuit and wherein the output of the three-level ac generating circuit is power grid.

Abstract: A power converter and a power converting method are provided. The power converter for converting an ac input voltage at an input terminal thereof into an ac output voltage at an output terminal thereof includes an energy-storing inductor, a first switching circuit coupled to the energy-storing inductor to selectively switch so that the input terminal of the power converter is coupled to the energy-storing inductor, a second switching circuit coupled to the energy-storing inductor and the first switching circuit to selectively switch so that a common terminal of the power converter is coupled to the energy-storing inductor; and a third switching circuit coupled to the energy-storing inductor, the first switching circuit and the second switching circuit to selectively switch so that the output terminal of the power converter is coupled to the energy-storing inductor.

Abstract: Parallel inverters without any communication buses and the controlling method thereof are provided. The parallel inverters are controlled by an instant voltage. Each inverter includes an output voltage waveform controller and a load-sharing controller. The output voltage waveform controller is connected to an output terminal of the inverter to control the waveform of an output voltage of the inverter. The load-sharing controller is connected to the output voltage waveform controller to control the load-sharing of the inverter and to make each inverter have the same phase, active power and reactive power without communications.

Abstract: A method of controlling an uninterruptible power supply apparatus (UPS) is provided. The UPS apparatus includes at least an AC input voltage, a DC input voltage and a single-phase AC/AC converter. The single-phase AC/AC converter includes an AC inductor, a bus capacitor, a boost arm, a common arm and a buck arm. The method includes steps of: controlling the bus voltage to have a DC component and full-wave rectifying component, and setting a bus voltage parameter K so that the bus voltage approaches to a full-wave rectifying voltage when K approaches to 1, wherein 0?K?1.

Abstract: A method for optimizing the optical disc writing parameters, comprising the steps: acquiring the variable of a mark runlength; determining a modulation amount of the writing parameters based on a relationship between the variable of the mark runlength and the modulation amount of the writing parameters; and modulating the writing parameters. The method is applicable to multifarious optical disc systems, it can adopt multifarious strategies for the writing process, it can optimize the power or the starting time and the stopping time of a plurality of laser pulses, thereby it can get the aim of optimizing the mark runlength.

Abstract: An integrated converter having three-phase power factor correction is provided. The integrated converter includes two PFC circuits. Two DC/DC converters are controlled and switched by the integrated converter in accordance with a three-phase AC power source so as to convert the AC power source into a DC power source. The use of the elements in the integrated converter is efficient.

Abstract: A kind of optical disc consists of the first layer, the second layer and the in-between layer, which lies between the first layer and the second layer. The first layer with its surface undulant includes material used to record information. The second layer with its surface basically flat includes material used to record information referring to the undulation of the first layer. The method to manufacture this optical disc comprises the steps of forming undulant first layer; forming the in-between layer on the surface of the first layer; and then forming the second layer. The first layer includes material used to record information, and the second layer includes material used to record information referring to the undulation of the first layer.

Abstract: A converting device with PFC and dc/dc converting functions is provided. The converting device includes a power source providing a dc voltage, an inverter having an input terminal electrically connected to the power source and an output terminal, a transformer having a primary winding electrically connected to the output terminal of the inverter and a secondary winding, a rectifier/filter circuit having an input terminal electrically connected to the secondary winding of the transformer and an output terminal, and a PFC converter coupled to the output terminal of the rectifier/filter circuit and having an input terminal receiving an ac input voltage. The converting device converts the ac input voltage into an ac output voltage when the ac input voltage is normal, and converts the dc voltage to output the ac output voltage with the cooperation of the inverter, the transformer, the rectifier/filter circuit and the PFC converter when the ac input voltage is abnormal.