Abstract: The present disclosure discloses a method for preparing a hierarchical porous material for a molecular sieve with an MFI structure. In the present disclosure, porous silicon dioxide is used as a carrier on a surface of which a nano zeolite seed is loaded, and then subjected to treatment with a secondary growth compound fluid and hydrothermal crystallization, so that a nano zeolite molecular sieve membrane is further grown on the surface of the porous silicon dioxide. The specific surface area and pore volume of the hierarchical porous material for the molecular sieve with the MFI structure prepared by the present disclosure are greatly improved compared with those of the original porous silicon dioxide. The material not only has the macroporous structure of the porous silicon dioxide, but also incorporates micropores of the molecular sieve itself and mesopores formed by molecular sieve agglomeration.

Abstract: Embodiments of this application disclose a tunnel establishment method. A first communication apparatus may receive first adjacency topology information sent by a second communication apparatus, and establish a first tunnel between the first communication apparatus and the second communication apparatus when the first adjacency topology information matches second adjacency topology information of the first communication apparatus. It can be learned that, in this solution, the first communication apparatus may locally store only the second adjacency topology information of the first communication apparatus. Compared with the conventional technology in which information about two endpoints of a tunnel needs to be configured on the first communication apparatus, configuration for the first communication apparatus is simpler.

Abstract: Disclosed by the present disclosure is a refrigerant leak detection method and device for an air conditioner. The method includes: acquiring current operating parameters of an air conditioner and environment information of a surrounding environment of the air conditioner; inputting the current operating parameters and the environment information into a trained neural network model to obtain an amount of remaining refrigerant outputted by the neural network model; and determining, according to the amount of the remaining refrigerant, whether there is a refrigerant leak in the air conditioner. The present disclosure improves accuracy of detecting a refrigerant leak in the air conditioner by means of an artificial neural network algorithm.

Abstract: A curve fitting method, apparatus and device based on a drawing tool for improving the accuracy of curve fitting. The method includes: determining a fitting area containing the original curve, in the fitting area, performing at least one sub-fitting operation on the original curve until the end condition of the curve fitting is satisfied, and generating a fitting curve corresponding to the original curve based on the fitting curve corresponding to each sub-fitting operation. This method can fit the original curve segments in the fitting area, which improves the accuracy of the obtained fitting curve.

Abstract: A hub image retrieval method and a device thereof for improving the retrieval accuracy of an image containing a hub. The method includes: performing feature extraction on a hub image to be processed containing a target hub, and obtaining a hub feature to be processed containing N sub-hub features, wherein the N sub-hub features at least include information characterizing the features of a hub window of the target hub; determining similarities between candidate hub features of each candidate hub image and the hub features to be processed; and selecting a candidate hub image matching the hub image to be processed from the plurality of candidate hub images based on the determined respective similarities.

Abstract: A fiber access terminal including a first assembly and a second assembly. The first assembly includes a first box body and an optical fiber adapter. The second assembly includes a second box body, an optical splitter, an optical fiber connector, and a plurality of optical fiber adapters. The optical fiber adapter of the first assembly is disposed outside the first box body. The optical splitter is disposed inside the second box body, and the optical fiber connector and the plurality of optical fiber adapters of the second assembly are disposed outside the second box body. A first end of the optical fiber connector is detachably connected to the optical fiber adapter of the first assembly, a second end of the optical fiber connector is connected to an input port of the optical splitter, and each output port is connected to one optical fiber adapter of the second assembly.

Abstract: The filter is provided, which includes a filter body and resonant cavities disposed on the filter body, and further includes an input port and an output port that are disposed on the filter body. At least one of the input port or the output port is connected to a set of additional resonant cavities, and each set of additional resonant cavities includes: a first additional resonant cavity in signal coupling to the input port or the output port, and a second additional resonant cavity in signal coupling to the first additional resonant cavity. In the filter, the two additional resonant cavities and another resonant cavity connected to the input port or the output port are in a form of a straight line, thereby implementing a flexible layout of cavities of the filter. In addition, a coupling structure is simple, costs are low, reliability and batch consistency is good.

Abstract: Aspects of the present disclosure provide techniques for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations.

Abstract: Disclosed by the present disclosure is a refrigerant leak detection method and device for an air conditioner. The method includes: acquiring current operating parameters of an air conditioner and environment information of a surrounding environment of the air conditioner; inputting the current operating parameters and the environment information into a trained neural network model to obtain an amount of remaining refrigerant outputted by the neural network model; and determining, according to the amount of the remaining refrigerant, whether there is a refrigerant leak in the air conditioner. The present disclosure improves accuracy of detecting a refrigerant leak in the air conditioner by means of an artificial neural network algorithm.

Abstract: A method of wirelessly communicating a packet includes generating, at a first wireless device, a first packet including a first preamble decodable by a plurality of devices and a second preamble decodable by only a subset of the plurality of devices. The first preamble includes a first signal field. The second preamble includes a first training field. The method further includes transmitting the first packet concurrently with one or more second packets to be transmitted by wireless devices other than the first wireless device.

Abstract: A fiber access terminal including a first assembly and a second assembly. The first assembly includes a first box body and an optical fiber adapter. The second assembly includes a second box body, an optical splitter, an optical fiber connector, and a plurality of optical fiber adapters. The optical fiber adapter of the first assembly is disposed outside the first box body. The optical splitter is disposed inside the second box body, and the optical fiber connector and the plurality of optical fiber adapters of the second assembly are disposed outside the second box body. A first end of the optical fiber connector is detachably connected to the optical fiber adapter of the first assembly, a second end of the optical fiber connector is connected to an input port of the optical splitter, and each output port is connected to one optical fiber adapter of the second assembly.

Abstract: A method of wirelessly communicating includes generating, at a wireless device, a packet including a first preamble field. The method further includes generating a first repeated preamble field by multiplying the first preamble field by a first frequency-domain polarity sequence. The method further includes transmitting the packet from the wireless device. The packet includes the first preamble field and the first repeated preamble field.

Abstract: Aspects of the present disclosure provide techniques for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations.

Abstract: A tunable filter includes a first waveguide body, a second waveguide body, a metal plate, a tuning piece, and a driving piece. A first cavity is disposed in the first waveguide body, and a second cavity is disposed in the second waveguide body. The metal plate is sandwiched between the first waveguide body and the second waveguide body, multiple windows are disposed on the metal plate, and the first cavity and the second cavity are in communication and are symmetrically distributed on both sides of the metal plate. The tuning piece includes a dielectric pull-rod and multiple metal sheets connected to the dielectric pull-rod, the dielectric pull-rod protrudes out of the first waveguide body and is connected to the driving piece, the multiple metal sheets are disposed inside the first cavity, and the multiple metal sheets are disposed corresponding to the multiple windows.

Abstract: Techniques are provided for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations. One technique includes generating a frame having a plurality of orthogonal training field sequences. Each orthogonal training field sequence is assigned to a different spatial stream. The frame is output for transmission as a single user (SU) transmission, a downlink multi-user (MU) multiple input multiple output (MIMO) transmission, or an orthogonal frequency division multiple access (OFDMA) transmission. After obtaining the frame, channel estimation and/or phase tracking may be performed based on the orthogonal training field sequences.

Abstract: Aspects of the present disclosure provide techniques for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations.

Abstract: The filter is provided, which includes a filter body and resonant cavities disposed on the filter body, and further includes an input port and an output port that are disposed on the filter body. At least one of the input port or the output port is connected to a set of additional resonant cavities, and each set of additional resonant cavities includes: a first additional resonant cavity in signal coupling to the input port or the output port, and a second additional resonant cavity in signal coupling to the first additional resonant cavity. In the filter, the two additional resonant cavities and another resonant cavity connected to the input port or the output port are in a form of a straight line, thereby implementing a flexible layout of cavities of the filter. In addition, a coupling structure is simple, costs are low, reliability and batch consistency is good.

Abstract: A method of wirelessly communicating a packet includes generating, at a first wireless device, a first packet including a first preamble decodable by a plurality of devices and a second preamble decodable by only a subset of the plurality of devices. The first preamble includes a first signal field. The second preamble includes a first training field. The method further includes transmitting the first packet concurrently with one or more second packets to be transmitted by wireless devices other than the first wireless device.

Abstract: A method of wirelessly communicating a packet including a first portion for transmission over at least one channel of a first transmission type and a second portion for transmission over at least one channel of a second transmission type. In one aspect, the method includes generating, at a wireless device, a packet including a first portion having a first symbol duration. The packet further includes a second portion having a second symbol duration greater than the first. The second portion can include a plurality of repeated portions of the signal field, the repeated portions having the second symbol duration. The first portion includes a first training field. The method further includes prepending or appending a second training field to the first portion. The second training field has the second symbol duration. The method further includes transmitting the packet.