Abstract: The present disclosure relates to a method for generating a novel impedance configuration for a three-degree-of-freedom (3DOF) leg of a hydraulically-driven legged robot. The method includes: separately determining variations of input signals of an inner position-based control loop and an inner force-based control loop of a hydraulic drive unit of each joint based on an obtained mathematical model; generating a novel impedance configuration in which position-based control is performed on a hydraulic drive unit of a hip joint, and force-based control is performed on hydraulic drive units of a knee joint and an ankle joint in a hydraulic drive system of the leg of a to-be-controlled robot; and performing forward calculation by using the leg mathematical model, to obtain an actual position and a force variation of the foot of the leg of the to-be-controlled robot to control motion of the foot of the to-be-controlled robot within motion space.

Abstract: Disclosed is a method for estimating database management system performance, in which a performance change ratio of a DBMS can be determined once a first knob group, a second knob group, and a data volume of active data in data managed by the DBMS are obtained, without actually configuring the second knob group in the DBMS, executing a job by the DBMS, and then observing the execution. In other words, the performance change ratio of the DBMS can be estimated without interacting with the DBMS. DBMS security can be ensured, performance measurement approaches are provided for self-tuning and self-management of the DBMS, and reliable and stable running of the DBMS is ensured.

Abstract: An active noise cancellation method and active noise cancellation earphones are provided, which may improve a noise cancellation effect of the active noise cancellation earphones. The method includes: determining a first primary path transfer function according to a first out-of-ear data collected by the out-of-ear microphone and a first in-ear data collected by the in-ear microphone when the speaker plays audio data; determining audio data received by the in-ear microphone according to the first in-ear data, the first out-of-ear data and the first primary path transfer function; determining a first secondary path transfer function according to the audio data played through the speaker and the audio data received by the in-ear microphone; and updating an operation coefficient of the filter to a first operation coefficient according to the first primary path transfer function and/or the first secondary path transfer function.

Abstract: A photodetector with an integrated reflective grating structure includes a substrate, an active layer disposed on the substrate, and a grating structure disposed between the substrate and the active layer. A first doped region is formed on the substrate at a location near the grating structure. A second doped region is formed on a surface of the active layer away from the grating structure. The doping type of the second doped region is different from that of the first doped region.

Abstract: Embodiments of the present application provide a method and system for active noise control, which can meet different needs of different consumers on sound quality of headphones. The method includes: determining an expected noise control curve of performing active noise control on a target object; determining a target filter according to the expected noise control curve and a filter model; and performing noise control processing on an external noise signal using the target filter.

Abstract: A method for controlling hybrid scanning based on a miniature reflecting device, which includes: loading parameters for determinant scanning and circular scanning, setting a scanning start point, and performing determinant scanning; performing low-pass filtering on received sampling data to filter an outlier in a sampling process, and performing singular value determining, to determine whether there is a valid connected domain within a scanning field of view; determining, as a target of interest, a valid connected domain with a maximum quantity of singular values, and obtaining a geometric center of the target of interest by calculating an average value of driving voltages corresponding to the singular values; performing circular scanning by using the geometric center as a scanning center, determining, in a process of scanning an outermost ring, whether singular values are centrosymmetrically distributed on the ring, to fine-tune the scanning center till the singular values are centrosymmetrically distributed

Abstract: Embodiments and methods perform ear cavity frequency response (EFCR) adaptive noise cancelation (ANC) with path-compensation over an entire main path to the eardrum (MPED) of a user. A number of ANC filter models are pre-trained to include respective anti-noise path (ANP) filter models and respective MPED filter models representing ANC filter configurations. As a user wears a headphone earpiece, characteristics of the wearer and the position/orientation of wearing manifest a wearer/wearing condition. Techniques described herein can continuously or periodically and efficiently determine which of the pre-trained ANC filter models most closely described the present MPED of the present wearer/wearing condition, and can continuously or periodically update the ANC filter configuration based on the pre-trained models to maintain high-performance ANC that includes EFCR path-compensation.

Abstract: A method for operating a software framework is provided. The method may be applied to a software framework applicable to a gateway device, the software framework includes an application service layer and a basic service layer, the application service layer includes at least one device service registered in advance, and the basic service layer includes a data bus built in advance. The method includes: realizing a capability of a device associated with the gateway device based on the device service; and realizing communication between the device service and an external service based on the data bus, where the external service includes a device service belonging to a same gateway device as the device service or a different gateway device than the device service.

Abstract: Embodiments and methods perform ear cavity frequency response (EFCR) adaptive noise cancelation (ANC) with path-compensation over an entire main path to the eardrum (MPED) of a user. A number of ANC filter models are pre-trained to include respective anti-noise path (ANP) filter models and respective MPED filter models representing ANC filter configurations. As a user wears a headphone earpiece, characteristics of the wearer and the position/orientation of wearing manifest a wearer/wearing condition. Techniques described herein can continuously or periodically and efficiently determine which of the pre-trained ANC filter models most closely described the present MPED of the present wearer/wearing condition, and can continuously or periodically update the ANC filter configuration based on the pre-trained models to maintain high-performance ANC that includes EFCR path-compensation.

Abstract: A method, device, and system for evaluating geological and engineering sweet spots in an unconventional reservoir based on dual-energy computed tomography (CT) comprises acquiring and preprocessing a high-energy CT image and a low-energy CT image of a core from a core region, acquiring and preprocessing a high-energy CT image and a low-energy CT image of a core from a core reference sample, calculating a density and an effective atomic number of each pixel in the core region of a target reservoir, acquiring a geological sweet spot index and an engineering sweet spot index, acquiring evaluation results of geological and engineering sweet spots at different depths of the core region in the target reservoir, and matching the evaluation results to acquire reservoir types corresponding to the different depths of the core region in the target reservoir. The present disclosure achieves accurate and efficient reservoir evaluation and classification.

Abstract: An optical bandpass filter includes an optical splitter having at least four ports, one of the ports being designated as an input port and one of the ports being designated as an output port. First and second reflectors couple with respective third and fourth ones of the ports. The splitter directs portions of the input light from the input port, into the third and fourth ports, such that the portions of the input light propagate toward the respective first and second reflectors. The first and second reflectors reflect light having wavelengths within a predetermined wavelength range, back toward the splitter, as wavelength-selected light, and transmit light having wavelengths that are outside of the predetermined wavelength range, away from the splitter. The splitter directs at least a portion of the wavelength-selected light that propagates back toward the splitter, into the output port, as output light.

Abstract: Systems, methods, and software can be used to provide reminding information. In some aspect, a special event is determined to occur. In response to determining that the special event occurs, a network type currently used by a device is acquired. Historical network usage information corresponding to the network type is determined. The network type and a traffic usage situation is outputted based on the historical usage information.

Abstract: Various embodiments disclose an electronic circuit for an electrochemical gas sensor. The electronic circuit comprises a first switching element electrically coupled to a reference terminal of the electrochemical gas sensor and a ground voltage terminal. Further, the electronic circuit comprises a second switching element electrically coupled to a sensing terminal of the electrochemical gas sensor and the ground voltage terminal. In an instance in which the electrochemical gas sensor is powered OFF, the first switching element and the second switching element are configured to electrically couple the reference terminal and the sensing terminal to the ground voltage terminal such that current generated when the sensing electrode and the target gas react while the electrochemical gas sensor is powered OFF flows to the ground voltage terminal and the potential of the reference terminal and the sensing terminal remain the equal.

Abstract: Disclosed is a method for estimating database management system performance, in which a performance change ratio of a DBMS can be determined once a first knob group, a second knob group, and a data volume of active data in data managed by the DBMS are obtained, without actually configuring the second knob group in the DBMS, executing a job by the DBMS, and then observing the execution. In other words, the performance change ratio of the DBMS can be estimated without interacting with the DBMS. DBMS security can be ensured, performance measurement approaches are provided for self-tuning and self-management of the DBMS, and reliable and stable running of the DBMS is ensured.

Abstract: A multifunctional experimental system for in-situ simulation of a gas hydrate includes a computed tomography (CT) scanning device, a reactor, and a pipeline system. The reactor includes: a reactor upper end cover, a reactor lower end cover, a reactor housing and a clamp holder. A first pipeline channel is formed at a top, an upper groove is formed at a bottom, and a first upper joint is arranged in the upper groove. A second pipeline channel is formed at a side, a lower groove is formed at a top, and a first lower joint is arranged in the lower groove; where two ends of the reactor housing are respectively fixed to the reactor upper end cover and the reactor lower end cover. A top end of the clamp holder is provided with a second upper joint, a bottom end of the clamp holder is provided with a second lower joint.

Abstract: A database processing method and an apparatus are provided, and may be applied to a database system. A tree structure is used to represent a join order and used as an input of a neural network, and different first attribute matrices are allocated to different brother nodes in the input tree structure. This helps the neural network comprehensively learn information about the join order, obtain representation information capable of differentiating the join order from another join order, and predict costs of the join order accurately based on the obtained representation information of the join order. Then, an optimizer selects a join order with lowest costs for a query statement based on the costs predicted by a cost prediction module.

Abstract: Some embodiments of the present disclosure provide a humidifier, the humidifier includes: a humidifier body, provided with a first air inlet; and an inner tub, provided in the humidifier body and internally provided with an air passage, a fan being provided in the air passage, the inner tub being provided with a second air inlet, the second air inlet and the first air inlet being communicated with an air inlet of the fan, and the portion of the inner tub above the second air inlet being provided with a blocking surface, which is provided opposite to at least a part of the first air inlet.

Abstract: A method for identifying a pore and a fracture based on a two-dimensional (2D) scan image of a core includes: scanning a core to acquire an initial 2D image of the core; filtering the initial 2D image of the core to acquire a first 2D image of the core; segmenting the first 2D image of the core to acquire a second 2D image of the core; extracting center coordinates of all pixel points in each void space to acquire a centroid of the void space, and establishing a pore-fracture identification function of the void space; identifying the void space as a fracture if a value of the pore-fracture identification function is greater than a preset characterization value; and identifying the void space as a pore if the value of the pore-fracture identification function is not greater than the preset characterization value.

Abstract: The present application belongs to the technical field of oil and gas exploration and development, and specifically provides a rock stratification identification method and apparatus, a device and a storage medium. The method includes: acquiring multiple sets of CT slice images of a rock, where each set of the CT slice images include a first CT slice image and a second CT slice image, the first CT slice image and the second CT slice image are acquired by scanning a same depth section of the rock, scanning energy corresponding to the first CT slice image is different form scanning energy corresponding to the second CT slice image; determining multiple dual energy indices of the rock according to the multiple sets of CT slice images; and determining a rock stratification according to the multiple dual energy indices, which can identify stratification of a large-scale rock by using CT.