Abstract: An air conditioning system is provided. The system has a high-pressure pipe, a low-pressure pipe, an indoor heat exchanger, an outdoor heat exchanger, a leak-free thermal expansion valve and a variable capacity compressor. The variable capacity compressor has a shell, a first cylinder and a second cylinder. The shell has a suction port and an exhaust port. The first cylinder has a first suction hole connected to the suction port and a first exhaust hole connected to the exhaust port. The second cylinder has a second suction hole connected to the suction port, a second exhaust hole connected to the exhaust port, and a pressure relief hole connected to the high-pressure pipe and the low-pressure pipe in an on-off manner. Before the variable capacity compressor is started, the high-pressure pipe and the low-pressure pipe are connected and also disconnected after the first preset duration.

Abstract: An air conditioning system is provided. The system has a high-pressure pipe, a low-pressure pipe, an indoor heat exchanger, an outdoor heat exchanger, a leak-free thermal expansion valve and a variable capacity compressor. The variable capacity compressor has a shell, a first cylinder and a second cylinder. The shell has a suction port and an exhaust port. The first cylinder has a first suction hole connected to the suction port and a first exhaust hole connected to the exhaust port. The second cylinder has a second suction hole connected to the suction port, a second exhaust hole connected to the exhaust port, and a pressure relief hole connected to the high-pressure pipe and the low-pressure pipe in an on-off manner. Before the variable capacity compressor is started, the high-pressure pipe and the low-pressure pipe are connected and also disconnected after the first preset duration.

Abstract: A frequency hopping communication method for short-distance wireless communication between a primary device and a secondary device comprises switching by the primary device from the second frequency hopping sequence to the first frequency hopping sequence at a time point of frequency hopping switching, wherein M reserved channels are between a first frequency hopping sequence and a second frequency hopping sequence; and performing frequency hopping communication with the secondary device based on the first frequency hopping sequence.

Abstract: A first device performs periodic scanning alternately, where a first scanning periodicity is used for a first-type Bluetooth connection, and a second scanning periodicity is used for a second-type Bluetooth connection; the first device receives a first-type data packet from a second device in a first scan window of any first scanning periodicity, where the first-type data packet is used to establish the first-type Bluetooth connection; the first device obtains, based on the first-type data packet, a second connection parameter for establishing the second-type Bluetooth connection to the second device; and the first device establishes the second-type Bluetooth connection to the second device based on the second connection parameter.

Abstract: The present disclosure relates to an image processing method and apparatus, an electronic device and a storage medium. The method comprises: extracting features from a to-be-processed image to so as to obtain a first feature of the image; determining the image category of the image according to the first feature and category center features of multiple reference image categories in a feature library; and in a case where the image category of the image is the first category of the multiple reference image categories, updating the category center feature of the first category according to the first feature and multiple pieces of feature information of the first category in the feature library. The method may improve the speed and accuracy of image retrieval.

Abstract: An air conditioning system is provided. The system has a high-pressure pipe, a low-pressure pipe, an indoor heat exchanger, an outdoor heat exchanger, a leak-free thermal expansion valve and a variable capacity compressor. The variable capacity compressor has a shell, a first cylinder and a second cylinder. The shell has a suction port and an exhaust port. The first cylinder has a first suction hole connected to the suction port and a first exhaust hole connected to the exhaust port. The second cylinder has a second suction hole connected to the suction port, a second exhaust hole connected to the exhaust port, and a pressure relief hole connected to the high-pressure pipe and the low-pressure pipe in an on-off manner. Before the variable capacity compressor is started, the high-pressure pipe and the low-pressure pipe are connected and also disconnected after the first preset duration.

Abstract: System and method for generating location-based alerts. An alert generation server communicates with official alert systems and a plurality of mobile devices operating a mobile alert application. The alert generation server receives alert data from the official alert systems and defines a plurality of alert events by extracting corresponding alert location information and assigning official alert types to the alerts in the received official alert data. The alert generation server also receives user-generated alert data defining alert events identified by mobile device users. The user-generated alert data is used to update and/or modify the defined alert events. Each alert event has a geographic region code corresponding to extracted alert location information. The mobile alert application determines, based on mobile device location data that the mobile device is within the geographic region of an alert event and generates an alert notification for that mobile device.

Abstract: A hybrid-driven cold/heat storage type heat pump unit utilizing a solar photovoltaic power and a commercial power, which has a DC compressor (2) and an AC compressor (8), is a dual supply heat pump system driven by a solar photovoltaic DC power and a common commercial AC power in combination. When there is sunshine, the DC generated by a solar cell panel (60) is used for driving the DC compressor (2) directly to produce cold and heat capacity, and the produced cold and heat capacity could be stored respectively in a phase-change cold storage medium (39) and a phase-change heat storage medium (20). When the DC power is insufficient, the AC power from power network is used for power supply.