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.

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: 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: 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: 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 x-ray analysis system with an x-ray source for producing an x-ray excitation beam directed toward an x-ray analysis focal area; and a sample chamber for presenting a fluid sample to the x-ray analysis focal area. The x-ray excitation beam is generated by an x-ray engine and passes through an x-ray transparent barrier on a wall of the chamber, to define an analysis focal area within space defined by the chamber. The fluid sample is presented as a stream supported in the space and streaming through the focal area, using a support structure to guide the sample stream. The chamber's barrier is therefore separated from both the focal area and the sample, resulting in lower corruption of the barrier.

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: An Internet protocol (IP) telephony system includes elements that prevent more than a specified number of simultaneous calls to be carried by the IP telephony system under a single user account. Multiple copies of a call session database are maintained in different geographical areas, and the multiple copies of the call session database are frequently and rapidly synchronized. The call session database is consulted before a new call is setup to determine if the user account that is to be used for the new call already is being used for a maximum number of simultaneous calls. If so, the new call setup request is denied.

Abstract: An x-ray analysis system with an x-ray source for producing an x-ray excitation beam directed toward an x-ray analysis focal area; and a sample chamber for presenting a fluid sample to the x-ray analysis focal area. The x-ray excitation beam is generated by an x-ray engine and passes through an x-ray transparent barrier on a wall of the chamber, to define an analysis focal area within space defined by the chamber. The fluid sample is presented as a stream suspended in the space and streaming through the focal area, using a laminar air flow and/or pressure to define the stream. The chamber's barrier is therefore separated from both the focal area and the sample, resulting in lower corruption of the barrier.

Abstract: An x-ray analysis system with an x-ray source for producing an x-ray excitation beam directed toward an x-ray analysis focal area; and a sample chamber for presenting a fluid sample to the x-ray analysis focal area. The x-ray excitation beam is generated by an x-ray engine and passes through an x-ray transparent barrier on a wall of the chamber, to define an analysis focal area within space defined by the chamber. The fluid sample is presented as a stream supported in the space and streaming through the focal area, using a support structure to guide the sample stream. The chamber's barrier is therefore separated from both the focal area and the sample, resulting in lower corruption of the barrier.

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: 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, the source spot requiring alignment along a transmission axis passing through the sample spot. A first housing section is provided, to which the x-ray tube is attached, including mounting features for adjustably mounting the x-ray tube therein such that the source spot coincides with the transmission axis. A second housing section includes a second axis coinciding with the transmission axis; and at least one x-ray optic attached to the second housing section for receiving the diverging x-ray beam and directing the beam toward the sample spot. Complimentary mating surfaces may be provided to align the first and second sections, and the optics, to the transmission axis. A third housing section may also be provided, including an aperture through which the x-ray beam passes, and to which a detector may be attached.

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, the source spot requiring alignment along a transmission axis passing through the sample spot. A first housing section is provided, to which the x-ray tube is attached, including mounting features for adjustably mounting the x-ray tube therein such that the source spot coincides with the transmission axis. A second housing section includes a second axis coinciding with the transmission axis; and at least one x-ray optic attached to the second housing section for receiving the diverging x-ray beam and directing the beam toward the sample spot. Complimentary mating surfaces may be provided to align the first and second sections, and the optics, to the transmission axis. A third housing section may also be provided, including an aperture through which the x-ray beam passes, and to which a detector may be attached.

Abstract: An x-ray analysis system with an x-ray source for producing an x-ray excitation beam directed toward an x-ray analysis focal area; and a sample chamber for presenting a fluid sample to the x-ray analysis focal area. The x-ray excitation beam is generated by an x-ray engine and passes through an x-ray transparent barrier on a wall of the chamber, to define an analysis focal area within space defined by the chamber. The fluid sample is presented as a stream suspended in the space and streaming through the focal area, using a laminar air flow and/or pressure to define the stream. The chamber's barrier is therefore separated from both the focal area and the sample, resulting in lower corruption of the barrier.

Abstract: A method, an apparatus and a computer program product for adaptive, content-based watermark embedding of a digital audio signal (100) are disclosed. Corresponding watermark extracting techniques are also disclosed. Watermark information (102) is encrypted (120) using an audio digest signal, i.e. a watermark key (108). To optimally balance inaudibility and robustness when embedding and extracting watermarks (450), the original audio signal (100) is divided into fixed-length frames (1100, 1120, 1130) in the time domain. Echoes (S′[n], S″[n]) are embedded in the original audio signal (100) to represent the watermark (450). The watermark (450) is generated by delaying and scaling the original audio signal (100) and embedding it in the audio signal (100). An embedding scheme (104) is designed for each frame (1100, 1120, 1130) according to its properties in the frequency domain.