Abstract: Methods, systems, and computer-readable storage media for providing a first instance of a database system within the cloud computing environment, determining that scale out of the database system is to be executed, and in response, providing a second instance of the database system within the cloud computing environment, the first instance and the second instance collectively defining a cluster, establish a remote direct memory access (RDMA) connection between the first instance and the second instance, copying data stored within the first instance to a data store of the second instance over the RDMA connection, and configuring the first instance to replicate a first transaction log to the second instance over the RDMA connection, and receiving, by each of the first instance and the second instance, requests from one or more client devices.

Abstract: A power line communication (PLC) system includes a PLC signal transmitting end, a PLC signal receiving end, and a power electronic apparatus. The PLC signal transmitting end is connected to the PLC signal receiving end through a power line, and the power electronic apparatus is connected to the power line. The power electronic apparatus is configured to increase output impedance in a first PLC communication frequency band, to reduce interference from an output current of the power electronic apparatus to a PLC signal in the first PLC communication frequency band. The first PLC communication frequency band is a PLC communication frequency band in which the PLC signal transmitting end sends the PLC signal to the PLC signal receiving end. In this way, the interference from the power electronic apparatus to the PLC signal in the first PLC communication frequency band can be reduced without adding an additional passive filter.

Abstract: A method for diagnosing lithium plating in lithium ion batteries includes performing electrochemical impedance spectroscopy analysis on complete or undisassembled lithium-ion batteries under different temperatures.

Abstract: A communication method includes a first network device that receives a service packet from a first endpoint device, where a destination media access control (MAC) address of the service packet is a specific local MAC address of a second endpoint device, the specific local MAC address includes an indication prefix and location information, the indication prefix indicates that the specific local MAC address includes the location information, and the location information indicates an access location of an endpoint device in a network. The first network device determines an egress port from a preset routing table based on the location information in the specific local MAC address of the second endpoint device, and sends the service packet through the egress port, where the routing table includes the location information and the egress port corresponding to the location information.

Abstract: Methods, systems, and computer-readable storage media for providing a first instance of a database system within the cloud computing environment, determining that scale out of the database system is to be executed, and in response, providing a second instance of the database system within the cloud computing environment, the first instance and the second instance collectively defining a cluster, establish a remote direct memory access (RDMA) connection between the first instance and the second instance, copying data stored within the first instance to a data store of the second instance over the RDMA connection, and configuring the first instance to replicate a first transaction log to the second instance over the RDMA connection, and receiving, by each of the first instance and the second instance, requests from one or more client devices.

Abstract: Methods, systems, and computer-readable storage media for receiving a query request including authorization data and a query, the authorization data indicating a privilege level index, determining a set of row ranges based on the privilege level index and a row range table, the set of row ranges including one or more row ranges having a privilege level associated therewith in the row range table, providing an initial results set including one or more records of a data table that are determined to be responsive, determining a final results set including at least one record of the initial results set, the at least one record being included in the final results set in response to determining that the at least one record is included in a row range of the set of row ranges, and outputting the final results set as at least a portion of a query result.

Abstract: A dynamic friction experimental device includes a base, an incident bar, an axial compression device, and a torque loading device. The base is provided with a displacement-constrain structure, and the incident bar includes a first incident section and a second incident section. The first incident section is arranged adjacent to the displacement-constrain structure, and the second incident section is connected to the first incident section. At a joint of the first incident section and the second incident section, a projection of a cross section of the first incident section is positioned in a cross section of the second incident section along an axial direction of the second incident section. When the dynamic mechanical property of a specimen is tested, the axial compression device is configured to apply pressure to the second incident section, and the torque loading device is configured to apply torque to the second incident section.

Abstract: A device for testing a needle roller bearing of a planet gear set consists of two identical helical planet gear sets, a piston, an end cover, a spindle, and can simulate the actual operating condition of a needle roller bearing of the planet gear set; the rotating speed difference between an inner raceway and an outer raceway of the needle roller bearing is determined by adjusting the rotating speed of a sun gear and a planet carrier; the load on the needle roller bearing includes a centrifugal load and a radial load, and the centrifugal acceleration and the centrifugal load are determined by adjusting the rotating speed of the planet carrier; a method of determining the radial load by adjusting the hydraulic pressure difference of hydraulic chambers at both ends of the piston, generating a tangential force to load the planet gear, and balancing the radial load of the bearing.

Abstract: The present disclosure discloses a phase-change flame-retardant fiber material for thermal management of a lithium ion battery in a closed space and a preparation method. The phase-change flame-retardant fiber material is prepared in a coaxial electrostatic spinning manner and includes a composite phase-change fiber material PASA-TPU at a core part and a flame-retardant fiber material TB-PAN wrapping a surface of the core part. The composite phase-change fiber material is well wrapped with the flame-retardant fiber material, and the lithium ion battery wrapping the whole phase-change flame-retardant fiber material in the closed space is subjected to charge-discharge cycle; the result shows that the surface temperature of the battery can be effectively reduced by about 20° C.

Abstract: An example system includes an inverter and at least one combiner box. The combiner box includes a plurality of direct current-direct current (DC-DC) circuits and one controller. The controller is configured to: when an output voltage of the combiner box is greater than or equal to a first preset voltage and less than or equal to a second preset voltage, control the combiner box to output a maximum power. When the output voltage of the combiner box is greater than the second preset voltage, the controller controls an output power of the combiner box to decrease as the output voltage increases. The second preset voltage is greater than the first preset voltage, and the maximum power is a sum of maximum powers of all photovoltaic strings connected to the combiner box.

Abstract: A device for testing a needle roller bearing of a planet gear set consists of two identical helical planet gear sets, a piston, an end cover, a spindle, and can simulate the actual operating condition of a needle roller bearing of the planet gear set; the rotating speed difference between an inner raceway and an outer raceway of the needle roller bearing is determined by adjusting the rotating speed of a sun gear and a planet carrier; the load on the needle roller bearing includes a centrifugal load and a radial load, and the centrifugal acceleration and the centrifugal load are determined by adjusting the rotating speed of the planet carrier; a method of determining the radial load by adjusting the hydraulic pressure difference of hydraulic chambers at both ends of the piston, generating a tangential force to load the planet gear, and balancing the radial load of the bearing.

Abstract: A common-mode voltage injection control method and apparatus for an inverter. For the method and apparatus, a common-mode voltage for a DPWM mode is calculated based on three-phase port voltages and an output power command; a common-mode voltage for an MPC modulation mode is calculated based on the direct current bus voltage, the three-phase port voltages, and the output power command; a modulation proportion is determined based on a maximum phase voltage peak value of the three-phase port voltages, the direct current bus voltage, and a power factor of the output power command; and a common-mode injection voltage is generated based on the common-mode voltage for the DPWM mode, the modulation proportion, and the common-mode voltage for the MPC modulation mode.

Abstract: The disclosure discloses a method for preparing a high-voltage cathode material by body modification and regeneration of a waste lithium cobaltate material.

Abstract: The present disclosure describes a method for repairing a cathode material of a spent lithium-ion battery, which includes: mixing the cathode material of the spent lithium-ion battery, a lithium sheet, a solid oxidant and absolute ethanol under a protective atmosphere for repairing to obtain a repaired cathode material of the lithium-ion battery, where a temperature for the repairing is 20-70° C.; a ratio of the amount of substance of lithium atoms to the total amount of substance of other metal atoms in the cathode material of the spent lithium-ion battery is (0.5-1):1, excluding 1:1.

Abstract: A wafer cleaning apparatus includes: a brush, configured to wash a surface to be cleaned of a wafer; a base for carrying the brush, the base having at least one conductive disk, a disk surface of the conductive disk being parallel to the surface to be cleaned, and the base being able to rotate around an axis of the base; and a magnetic field generation structure configured to emit, to the conductive disk, a magnetic field perpendicular to the disk surface of the conductive disk, so that an induced electric field is generated in the conductive disk during the rotation of the base. The quality of wafer cleaning and the yield of wafer products can be improved.

Abstract: A preparing method for high-purity levetiracetam, comprising: adjusting the pH of an extracted aqueous layer obtained by dissociating (S)-?-ethyl-2-oxo-1-pyrrolidineacetic acid (R)-methylbenzylamine salt to 5-9; removing water; adding an organic solvent to form a solution and then performing an esterification reaction with ethyl chloroformate or methylchlorofonmate; and carrying out an ammonolysis reaction to obtain the levetiracetam. The method simplifies production process, increases yield, reduces or even avoids the use of triethylamine in the esterification process, and reduces the emission of a great amount of three wastes.

Abstract: A method for synthesizing valsartan, comprising the steps of: synthesizing a valsartan methyl ester intermediate to obtain a reaction mixture of the valsartan methyl ester intermediate; diluting the reaction mixture by salt water or water, and then using a first extraction solvent to extract the valsartan methyl ester intermediate; adding alkali to an organic layer containing the valsartan methyl ester intermediate for hydrolyzing, removing the organic layer, regulating pH of a water layer to be acidic by using acid, using the first extraction solvent to extract, concentrating a part of solvent, or distilling the solvent to dryness, and then adding a new solvent; finally, crystallizing, filtering, and drying to obtain the valsartan.

Abstract: A wafer cleaning apparatus includes: a brush, configured to wash a surface to be cleaned of a wafer; a base for carrying the brush, the base having at least one conductive disk, a disk surface of the conductive disk being parallel to the surface to be cleaned, and the base being able to rotate around an axis of the base; and a magnetic field generation structure configured to emit, to the conductive disk, a magnetic field perpendicular to the disk surface of the conductive disk, so that an induced electric field is generated in the conductive disk during the rotation of the base. The quality of wafer cleaning and the yield of wafer products can be improved.

Abstract: A processor may receive a recording. The recording may include one or more user guidance sequences and be displayed to a user. The processor may receive a first user input response to an initiation of a first user guidance sequence. The processor may determine, in response to receiving the first user input, that there is a discrepancy between the first user input and the first user guidance sequence. The processor may automatically modify the playback setting of the recording. The processor may display the discrepancy between the first user input and the first user guidance sequence to the user.

Abstract: A calcium-bearing magnesium and rare earth element alloy consists essentially of, in mass percent, zinc (Zn): 1-3%; aluminum (Al): 1-3%; calcium (Ca): 0.1-0.4%; gadolinium (Gd): 0.1-0.4%; yttrium (Y): 0-0.4%; manganese (Mn): 0-0.2%; and balance magnesium (Mg).