Abstract: An artificial intelligence (AI)-based audio signal generation method includes: converting a text into a corresponding phoneme sequence; encoding the phoneme sequence to obtain a contextual representation of the phoneme sequence; determining, based on a first frame hidden state corresponding to a phoneme in the phoneme sequence, an alignment position of the first frame hidden state relative to the contextual representation; decoding the contextual representation and the first frame hidden state to obtain a second frame hidden state when the alignment position corresponds to a non-end position in the contextual representation; and synthesizing the first frame hidden state and the second frame hidden state to obtain an audio signal corresponding to a text.

Abstract: An HVAC system utilizes one or more modular heat pump units installed within an outer wall or corner of a building, and one or more active registers. A central hub, which can be integrated into a modular HVAC unit, receives input from thermostats and sensors in the building and adjusts operation of the modular HVAC units and active registers to distribute conditioned air throughout the building. The system provides convenience and comfort of a traditional split HVAC system with significantly reduced installation and maintenance costs. The modular HVAC unit includes an interchangeable cartridge that contains the active components of a heat pump. Cartridges of different capacities can be installed as required, and are easily swapped out for maintenance, servicing, and replacement. A user can control the system using traditional-style thermostats and with a smart phone, tablet or computer. A cloud server provides backup services and remote access to the system.

Abstract: An HVAC system utilizes one or more modular heat pump units installed within an outer wall or corner of a building, and one or more active registers. A central hub, which can be integrated into a modular HVAC unit, receives input from thermostats and sensors in the building and adjusts operation of the modular HVAC units and active registers to distribute conditioned air throughout the building. The system provides convenience and comfort of a traditional split HVAC system with significantly reduced installation and maintenance costs. The modular HVAC unit includes an interchangeable cartridge that contains the active components of a heat pump. Cartridges of different capacities can be installed as required, and are easily swapped out for maintenance, servicing, and replacement. A user can control the system using traditional-style thermostats and with a smart phone, tablet or computer. A cloud server provides backup services and remote access to the system.

Abstract: An HVAC system utilizes one or more modular heat pump units installed within an outer wall or corner of a building, and one or more active registers. A central hub, which can be integrated into a modular HVAC unit, receives input from thermostats and sensors in the building and adjusts operation of the modular HVAC units and active registers to distribute conditioned air throughout the building. The system provides convenience and comfort of a traditional split HVAC system with significantly reduced installation and maintenance costs. The modular HVAC unit includes an interchangeable cartridge that contains the active components of a heat pump. Cartridges of different capacities can be installed as required, and are easily swapped out for maintenance, servicing, and replacement. A user can control the system using traditional-style thermostats and with a smart phone, tablet or computer. A cloud server provides backup services and remote access to the system.

Abstract: A heating, ventilation, and/or air conditioning (HVAC) system may include a heat exchanger comprising at least one heat exchanger tube. The heat exchanger tube may include multiple passes: a first pass, a second pass having an elliptical portion with dimples disposed in the elliptical portion, and a third pass having an elliptical portion with dimples disposed in the elliptical portion. The first pass and the second pass may be connected in fluid communication by a first bend, and the second pass and the third pass may be connected in fluid communication by a second bend. The heat exchanger tube may be configured to promote heat transfer while also controlling a pressure drop across the heat exchanger tube.