Abstract: An islanding detection method and apparatus for an inverter, and a power supply system to resolve a problem that an existing voltage total harmonic distortion (THD)-based islanding detection method has low islanding detection reliability due to existence of a relatively large detection dead zone. According to this detection method, the voltage total harmonic distortion changes more significantly before and after the islanding effect of the inverter occurs in order to reduce an islanding detection dead zone and improve islanding detection reliability.

Abstract: A support structure having multiple highly aligned curved x-ray optics, the support structure having multiple internal partially or fully concentric surfaces upon which said optics are mounted, thereby aligning said optics along a central optical axis thereof and therefore to a source, sample, and/or detector in combination with which the support structure is useable. The surfaces may be nested around the central optical axis; and the support structure may divided longitudinally into sections around the central optical axis by walls. At least one of the x-ray optics comprises a curved diffracting optic, for receiving a diverging x-ray beam and focusing the beam to a focal area, in one embodiment a focusing monochromating optic. In an improved embodiment, an optic comprises a single layer, plastically deformed, LiF optic.

Abstract: A service control method and a service control apparatus, where the method includes obtaining, a current electricity grid electricity price and a quantity of to-be-executed services, determining an electricity price threshold according to the quantity of the to-be-executed services, decreasing, by the service control apparatus, a quantity of services that are about to be executed by a first quantity when the current electricity grid electricity price is greater than the electricity price threshold, and executing a service according to a reduced quantity of services that are about to be executed, or increasing, by the service control apparatus, a quantity of services that are about to be executed by a second quantity, and executing a service according to an increased quantity of services that are about to be executed when the current electricity grid electricity price is less than the electricity price threshold.

Abstract: A power converter, including: at least two inverting modules, where direct current sides of the at least two inverting modules are connected in parallel using a laminated busbar or a circuit board, and the at least two inverting modules run in an interleaved and parallel manner. In the present invention, the power converter is formed by connecting at least two inverting modules in parallel, and the direct current sides of the at least two inverting modules are connected in parallel using the laminated busbar or the circuit board, so that parasitic inductance between inverting modules is small, forming a low parasitic inductance loop. When the at least two inverting modules run in an interleaved and parallel manner, the low parasitic inductance loop counteracts most ripple currents in a circuit, thereby reducing the burden of the ripple currents on a bus capacitor. Therefore, the demand of the power converter provided in the present invention for the bus capacitor is small.

Abstract: The present application provides a low voltage ride-through control system for a multi-inverter grid-connected power converter, including: a photovoltaic array and an inverter. The inverter includes a DC/DC conversion unit and a DC/AC inversion unit connected to an output end of the DC/DC conversion unit, an input end of the DC/DC conversion unit is connected to an output end of the photovoltaic array, and the inverter is connected to a power grid at a grid-connected point. The inverter further includes a low voltage ride-through detection unit and a low voltage ride-through control unit. The low voltage ride-through detection unit is configured to determine whether to trigger low voltage ride-through. The low voltage ride-through control unit is configured to lower an input voltage of the DC/DC conversion unit when it is determined to trigger the low voltage ride-through, to lower an output voltage of the photovoltaic array.

Abstract: The present disclosure relates to the field of inverters, and to a method for detecting grid connection stability of an inverter and an inverter. The method includes: detecting a line voltage and a current of the alternating current port to obtain a first group of line voltage values and a first group of current values; detecting the line voltage and the current of the alternating current port to obtain a second group of line voltage values and a second group of current values; obtaining an equivalent impedance matrix of the power grid according to the first group of line voltage values, the first group of current values, the second group of line voltage values, and the second group of current values; and determining, by the inverter according to an equivalent admittance matrix and the equivalent impedance matrix, whether a stability requirement of the inverter is met.

Abstract: An inverter control method, apparatus, and system are provided. The method in the embodiments of the present invention includes obtaining power distribution line graph of an inverter switch according to an output power and an input voltage that are of an inverter; when an area to which the inverter belongs is a first area and the inverter switch works at a second frequency, switching the inverter switch to a first frequency; and when the area to which the inverter belongs is a second area and the inverter switch works at the first frequency, switching the inverter switch to the second frequency. In the embodiments of the present invention, whether a working frequency of an inverter switch needs to be changed is determined according to an output power and an input voltage, which improves control efficiency, thereby effectively improving conversion efficiency of an inverter.

Abstract: A support structure having multiple highly aligned curved x-ray optics, the support structure having multiple internal partially or fully concentric surfaces upon which said optics are mounted, thereby aligning said optics along a central optical axis thereof and therefore to a source, sample, and/or detector in combination with which the support structure is useable. The surfaces may be nested around the central optical axis; and the support structure may divided longitudinally into sections around the central optical axis by walls. At least one of the x-ray optics comprises a curved diffracting optic, for receiving a diverging x-ray beam and focusing the beam to a focal area, in one embodiment a focusing monochromating optic. In an improved embodiment, an optic comprises a single layer, plastically deformed, LiF optic.

Abstract: An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced having a characteristic first energy, and bremsstrahlung energy; a first x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam; and a second x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam to a second energy. The first x-ray optic may monochromate characteristic energy from the source spot, and the second x-ray optic may monochromate bremsstrahlung energy from the source spot. The x-ray optics may be curved diffracting optics, for receiving the diverging x-ray beam from the x-ray tube and focusing the beam at the sample spot. Detection is also provided to detect and measure various toxins in, e.g., manufactured products including toys and electronics.

Abstract: Methods and systems for voice and video messaging are provided here. In some embodiments a method for voice and video messaging may include establishing a telecommunication session with a calling device associated with a first user in response to an indication that a call request from the calling device directed to a called identifier associated with a second user failed, providing to the calling device an option to leave a video message and an option to leave an audio message, receiving a selection from the calling device indicating the selection of the option to leave a video message, disconnecting the established telecommunication session, and receiving a video message from the calling device.

Abstract: An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced having a characteristic first energy, and bremsstrahlung energy; a first x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam; and a second x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam to a second energy. The first x-ray optic may monochromate characteristic energy from the source spot, and the second x-ray optic may monochromate bremsstrahlung energy from the source spot. The x-ray optics may be curved diffracting optics, for receiving the diverging x-ray beam from the x-ray tube and focusing the beam at the sample spot. Detection is also provided to detect and measure various toxins in, e.g., manufactured products including toys and electronics.

Abstract: A channel and noise estimation method includes: performing channel estimation on a received signal to obtain a real channel estimation value; filtering the real channel estimation value to obtain a filtered channel estimation value; calculating a biased noise power value, a biased signal power value, a biased noise correlation and a biased signal correlation according to the filtered channel estimation value; calculating an unbiased noise power value, an unbiased signal power value, an unbiased noise correlation and an unbiased signal correlation according to the biased noise power value, the biased signal power value, the biased noise correlation and the biased signal correlation.

Abstract: An inverter control method, apparatus, and system are provided. The method in the embodiments of the present invention includes obtaining power distribution line graph of an inverter switch according to an output power and an input voltage that are of an inverter; when an area to which the inverter belongs is a first area and the inverter switch works at a second frequency, switching the inverter switch to a first frequency; and when the area to which the inverter belongs is a second area and the inverter switch works at the first frequency, switching the inverter switch to the second frequency. In the embodiments of the present invention, whether a working frequency of an inverter switch needs to be changed is determined according to an output power and an input voltage, which improves control efficiency, thereby effectively improving conversion efficiency of an inverter.

Abstract: Methods and systems for voice and video messaging are provided here. In some embodiments a method for voice and video messaging may include establishing a telecommunication session with a calling device associated with a first user in response to an indication that a call request from the calling device directed to a called identifier associated with a second user failed, providing to the calling device an option to leave a video message and an option to leave an audio message, receiving a selection from the calling device indicating the selection of the option to leave a video message, disconnecting the established telecommunication session, and receiving a video message from the calling device.

Abstract: The Internet Protocol telephony system comprises a registration unit; a signal handling interface; a rules engine; and a call processing interface. The registration unit is configured to store, in association with a customer record, a notification list of one or more telephony devices that that are to be notified upon receipt by the Internet Protocol telephony system of a communication addressed to a customer identifier corresponding to the customer record. The signal handling interface is configured to receive a signal originated by a telephony device. The rules engine is configured to consult the notification list and apply rules logic to determine in what order the one or more telephony devices on the notification list are to be notified. The call processing interface is configured to route notifications to the one or more telephony devices.

Abstract: A telephony system (20) comprises a computer-implemented call forwarding verification system (60) configured to initiate a test call to a telephony device (30) in conjunction with a request for a call forwarding operation. The request for the call forwarding operation is configured to instruct that a subsequent call to the telephony device be directed to a forwarding number. Preferably the forwarding number is a number associated with the telephony system (20).

Abstract: Methods and systems for managing voicemail operations are provided here. In some embodiments a method for managing voicemail operations may include establishing a voicemail session with a voicemail system, transmitting message data over the voicemail session to be recorded in a voicemail message for a second user on the voicemail system, receiving an incoming call from a device associated with the second user while the voicemail session is active, and sending a first notification to the voicemail system to manage the voicemail message prior to establishing the incoming call with the device associated with the second user.

Abstract: An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced having a characteristic first energy, and bremsstrahlung energy; a first x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam; and a second x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam to a second energy. The first x-ray optic may monochromate characteristic energy from the source spot, and the second x-ray optic may monochromate bremsstrahlung energy from the source spot. The x-ray optics may be curved diffracting optics, for receiving the diverging x-ray beam from the x-ray tube and focusing the beam at the sample spot. Detection is also provided to detect and measure various toxins in, e.g., manufactured products including toys and electronics.

Abstract: A power converter, including: at least two inverting modules, where direct current sides of the at least two inverting modules are connected in parallel using a laminated busbar or a circuit board, and the at least two inverting modules run in an interleaved and parallel manner. In the present invention, the power converter is formed by connecting at least two inverting modules in parallel, and the direct current sides of the at least two inverting modules are connected in parallel using the laminated busbar or the circuit board, so that parasitic inductance between inverting modules is small, forming a low parasitic inductance loop. When the at least two inverting modules run in an interleaved and parallel manner, the low parasitic inductance loop counteracts most ripple currents in a circuit, thereby reducing the burden of the ripple currents on a bus capacitor. Therefore, the demand of the power converter provided in the present invention for the bus capacitor is small.

Abstract: An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced having a characteristic first energy, and bremsstrahlung energy; a first x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam; and a second x-ray optic receives the diverging x-ray beam and directs the beam toward the sample spot, while monochromating the beam to a second energy. The first x-ray optic may monochromate characteristic energy from the source spot, and the second x-ray optic may monochromate bremsstrahlung energy from the source spot. The x-ray optics may be curved diffracting optics, for receiving the diverging x-ray beam from the x-ray tube and focusing the beam at the sample spot. Detection is also provided to detect and measure various toxins in, e.g., manufactured products including toys and electronics.