Abstract: A method for recommending text information, a server, a browser, and a system thereof are provided. The method includes: a keyword is obtained by a server from a text index pool in response to a visiting request for a webpage from a browser; a recommended text information list is obtained from the text index pool according to the corresponding keyword; the recommended text information list is embedded into the webpage and the webpage is returned to the browser for displaying to a user; and the user may click the keyword to obtain the recommended text information list as required, thereby the keyword is set as the connection between the user and the webpage text information.

Abstract: A method for improving a power converter's efficiency comprises detecting an input voltage of a power converter, determining an operation mode of the power converter based upon the input voltage of the power converter and generating a plurality of gate drive signals based upon a damped gain control, wherein the damped gain control is configured such that an output voltage of the power converter is in a range from a tightly regulated output voltage to an unregulated output voltage.

Abstract: A power system comprising a non-isolated voltage regulator configured to couple to an input voltage and produce an output voltage, wherein the non-isolated voltage regulator is in a power distribution system and configured to boost the input voltage when the input voltage is less than a minimum output voltage, to reduce the input voltage when the input voltage is greater than a maximum output voltage, and to pass-through the input voltage when the input voltage is greater than or equal to the minimum output voltage and less than or equal to the maximum output voltage.

Abstract: An apparatus comprising a first rectifier, wherein an output of the first rectifier is coupled to a first terminal, a second rectifier, wherein an output of the second rectifier is coupled to a second terminal, a first electronic switch configured to selectively route an alternating current (AC) signal to the first rectifier or the second rectifier, an inverter configured to operate in the event that the first electronic switch does not receive the AC signal to receive a direct current (DC) signal, and convert the DC signal to a second AC signal, a second electronic switch configured to selectively route the DC signal from the first terminal or the second terminal to the inverter, and a third electronic switch configured to selectively route the second AC signal to the first rectifier or the second rectifier.

Abstract: An embodiment common mode noise reduction apparatus comprises a common mode choke, a balance inductor, a first capacitor and a second capacitor. The common mode choke is placed between an input dc source and a primary side network of an isolated power converter. The balance inductor is coupled between an upper terminal of a primary winding of the isolated power converter and a negative terminal of the input dc source. The first capacitor is coupled between the upper terminal of a primary side of a transformer and an upper terminal of a secondary side of the transformer of the isolated power converter. The second capacitor is coupled between a lower terminal of the primary side of the transformer and a lower terminal of the secondary side of the transformer of the isolated power converter.

Abstract: A soft switching apparatus comprises an energy recovery channel formed by two diodes in series connection and a resonant tank formed by an inductor and a capacitor. The soft switching apparatus is coupled to the primary side of a bridge converter. An energy transfer process during L-C resonance helps to reduce the amplitude of the current flowing through the inductor in a freewheeling period. Furthermore, the soft switching apparatus can help to reduce the voltage stress across the secondary switching devices as well as the shoot-through currents flowing through the secondary switching devices, and thus enabling the reduction or elimination of dead time in a secondary synchronous rectifier control scheme.

Abstract: An embodiment hybrid dc/dc converter comprises a first power source and a low power converter coupled to the first power source. The low power converter generates an output connected in series with the first power source. The hybrid dc/dc converter further comprises a selection network coupled to the first power source and the output of the low power converter and a main unregulated power converter coupled to the selection network. By controlling the voltage across the output of the low power converter, the hybrid dc/dc converter can achieve high efficiency through the unregulated power converter.

Abstract: An embodiment holdup time circuit of a bridgeless power factor correction circuit comprises a charge device, an energy storage apparatus and a discharge device. The charge device comprises a first terminal coupled to a bridgeless power factor correction circuit and a second terminal coupled to the energy storage apparatus. The discharge device comprises a first terminal coupled to the energy storage apparatus and a second terminal coupled to the bridgeless power factor correction circuit.

Abstract: An embodiment bridgeless power factor correction circuit comprises a first boost converter and a second boost converter connected in parallel. A first switch is coupled between the input of the first boost converter and ground. A second switch is coupled between the input of the second boost converter and ground. Both the first switch and the second switch help to reduce the common mode noise of the bridgeless power factor correction circuit. The bridgeless power factor correction circuit further comprises two surge protection diodes coupled between the inputs of two boost converters and the output of the bridgeless power factor correction circuit.

Abstract: An embodiment bridgeless power factor correction circuit comprises a first boost converter and a second boost converter connected in parallel. A first switch is coupled between the input of the first boost converter and ground. A second switch is coupled between the input of the second boost converter and ground. Both the first switch and the second switch help to reduce the common mode noise of the bridgeless power factor correction circuit. The bridgeless power factor correction circuit further comprises two surge protection diodes coupled between the inputs of two boost converters and the output of the bridgeless power factor correction circuit.

Abstract: An embodiment power converter package comprises a semiconductor die, an output inductor, a plurality of input capacitors and output capacitors. The semiconductor die, the output inductor and the plurality of capacitors are mounted on a lead frame and connected one to another through various pads on the lead frame. The semiconductor die comprises a high side switch, a low side switch and a driver. The power converter package is electrically coupled to an external pulse width modulation controller through a variety of input and output pads.

Abstract: A soft switching apparatus comprises an energy recovery channel formed by two diodes in series connection and a resonant tank formed by an inductor and a capacitor. The soft switching apparatus is coupled to the primary side of a bridge converter. An energy transfer process during L-C resonance helps to reduce the amplitude of the current flowing through the inductor in a freewheeling period. Furthermore, the soft switching apparatus can help to reduce the voltage stress across the secondary switching devices as well as the shoot-through currents flowing through the secondary switching devices, and thus enabling the reduction or elimination of dead time in a secondary synchronous rectifier control scheme.

Abstract: An embodiment common mode noise reduction apparatus comprises a common mode choke, a balance inductor, a first capacitor and a second capacitor. The common mode choke is placed between an input dc source and a primary side network of an isolated power converter. The balance inductor is coupled between an upper terminal of a primary winding of the isolated power converter and a negative terminal of the input dc source. The first capacitor is coupled between the upper terminal of a primary side of a transformer and an upper terminal of a secondary side of the transformer of the isolated power converter. The second capacitor is coupled between a lower terminal of the primary side of the transformer and a lower terminal of the secondary side of the transformer of the isolated power converter.

Abstract: A power system comprising a non-isolated voltage regulator configured to couple to an input voltage and produce an output voltage, wherein the non-isolated voltage regulator is in a power distribution system and configured to boost the input voltage when the input voltage is less than a minimum output voltage, to reduce the input voltage when the input voltage is greater than a maximum output voltage, and to pass-through the input voltage when the input voltage is greater than or equal to the minimum output voltage and less than or equal to the maximum output voltage.

Abstract: A CNC system can include a cylinder adapted to rotate about, travel along, and deliver a force in an axial direction, an extension coupled to a distal end of and extending outward from the elongated component in a direction perpendicular to the axial direction, and a removable fixture adapted to receive the axial force and to be moved and positioned thereby along a plane (i.e., two directions) substantially perpendicular to the axial direction. The fixture has a central opening along the first direction adapted to receive the elongated component, and includes external features adapted to guide manufacturing operations for other manufacturing components. Chamfers on both the extension and removable fixture convert the downward axial force into a plurality of lateral forces that move the fixture against a receiver base. Datums located at guide holes in the fixture stop such lateral movement when the movement causes them to contact guide pins coupled to the receiver base.

Abstract: The present invention relates to a method of forming a 1,3-diamino-3-substituted-2-propanol chemical intermediate from which various chemicals, such as selected protease-inhibitors and other drugs, as well as polymers, can be synthesized.The method includes contacting a nitromethyl amino acid compound with at least one reducing agent to form the 1,3-diamino-3-substituted-2-propanol chemical intermediate.

Abstract: The present invention relates to a method of forming a 1,3-diamino-3-substituted-2-propanol chemical intermediate from which various chemicals, such as selected protease-inhibitors and other drugs, as well as polymers, can be synthesized.This method includes contacting a nitromethyl amino acid compound with at least one reducing agent to form the 1,3-diamino-3-substituted-2-propanol chemical intermediate.

Abstract: The present invention relates to a method of forming a 1,3-diamino-3-substituted-2-propanol chemical intermediate from which various chemicals, such as selected protease-inhibitors and other drugs, as well as polymers, can be synthesized.This method includes contacting a nitromethyl amino acid compound with at least one reducing agent to form the 1,3-diamino-3-substituted-2-propanol chemical intermediate.

Abstract: The present invention relates to a method of forming a 1,3-diamino-3-substituted-2-propanol chemical intermediate from which various chemicals, such as selected protease-inhibitors and other drugs, as well as polymers, can be synthesized.This method includes contacting a nitromethyl amino acid compound with at least one reducing agent to form the 1,3-diamino-3-substituted-2-propanol chemical intermediate.

Abstract: Stereoisomeric substituted and/or unsubstituted octahydronaphthoquinolizines (OHNQs), and derivatives and analogs thereof are provided, including pharmaceutical and diagnostic compositions, as well as methods of making and using these compounds according to the following formula I: ##STR1##