Abstract: The field of metal hoses, and specifically, an explosion-proof flexible metal hose for natural gas pipelines is concerned. The problems that the existing metal hose has low intensity and high flow velocity are solved. The explosion-proof flexible metal hose for natural gas pipelines includes a metal hose. A side of the metal hose is provided with a fixing assembly composed of a flange and a loose flange, and an other side of the metal hose is provided with a welding neck flange configured for fixing. The metal hose is covered with a steel band with a multilayer structure. The metal hose and two ends of the steel band are fixed through cooperation between metal short sections and pressing clamp rings. A reinforcement coil is wound around the metal hose.

Abstract: The field of metal hoses, and specifically, an explosion-proof flexible metal hose for natural gas pipelines is concerned. The problems that the existing metal hose has low intensity and high flow velocity are solved. The explosion-proof flexible metal hose for natural gas pipelines includes a metal hose. A side of the metal hose is provided with a fixing assembly composed of a flange and a loose flange, and an other side of the metal hose is provided with a welding neck flange configured for fixing. The metal hose is coverd with a steel band with a multilayer structure. The metal hose and two ends of the steel band are fixed through cooperation between metal short sections and pressing clamp rings. A reinforcement coil is wound around the metal hose. According to the device, the existing metal hose structure is optimized. The reinforcement coil is designed in the metal hose, so that the intensity of the metal hose is improved, and a dual anti-explosion effect of the metal hose is achieved.

Abstract: A channel structure that can efficiently transmit more data control bits, e.g., required by future wireless communication systems, yet achieve sufficient detection and false alarm performance uses tail-biting convolutional coding and Cyclical Redundancy Check (CRC). In certain implementations, symbol repetition, interleaving and/or scrambling can also be included. Also, depending on the implementation, modulation schemes such as Bi-Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK) or Quadrature Amplitude Modulation (QAM) can be used in conjunction with the other coding techniques.

Abstract: A preamble channel encoder, e.g., in a UHDR-DO system, uses a channel structure that can efficiently transmit more information bits, yet achieve sufficient detection and false alarm performance. The preamble channel encoder uses tail-biting convolutional coding and Cyclical Redundancy Check (CRC). The preamble channel structure can be used to encode, e.g., rate indicator bits, while a MAC identifier encoder, e.g., a Reed-Solomon encoder, is used to encode MAC identifier bits. The encoded rate indictor and MAC identifier bits can then be mapped to the appropriate tones in an OFDM encoding scheme.

Abstract: A channel structure that can efficiently transmit more data control bits, e.g., required by future wireless communication systems, yet achieve sufficient detection and false alarm performance uses tail-biting convolutional coding and Cyclical Redundancy Check (CRC). In certain implementations, symbol repetition, interleaving and/or scrambling can also be included. Also, depending on the implementation, modulation schemes such as Bi-Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK) or Quadrature Amplitude Modulation (QAM) can be used in conjunction with the other coding techniques.