Abstract: Disclosed herein is a system for measuring a microwave dielectric property of a solid material under force. The system measures the microwave dielectric property of the solid material under a horizontal pressure. A shield case for microwave electromagnetic shielding is provided outside the system. The shield case includes a layer of pure aluminum and a layer of pyramids made of a microwave absorbing material. A manual hydraulic pump controls loading and unloading of a pressure loading device.

Abstract: Downhole tractor control systems and methods to maintain a load of a downhole tractor are disclosed. A method to maintain a load of a downhole tractor includes identifying a reduction of power of a first set of motors of a plurality of motors of the downhole tractor, determining whether the reduction of power of the first set of motors is below a first threshold, and increasing, in response to the determination, a first power limit of a second set of motors of the plurality of motors to a maximum acceptable power limit of the second set of motors while maintaining the load of the downhole tractor.

Abstract: A motor detection method includes the following steps. An excitation current command is provided to a motor device, and the motor device is driven to rotate at the first angle. The first feedback angle of the motor device in the first resting position is detected and obtained. The motor device is driven to rotate at the second angle according to the excitation current command. The second feedback angle of the motor device in the second resting position is detected and obtained. The magnetic pole offset angle of the motor device is calculated according to the first feedback angle and the second feedback angle.

Abstract: A method of estimating and compensating an interference torque of a lifting system includes steps of: continuously integrating a speed of a motor and specifying an integration value to be zero if the integration value is negative when the elevator car moves upward and downward in a hoist way; estimating a rope load constant of a wire rope according to an initial position and a maximum travel position, and calculating a rope load torque according to the maximum travel position, the rope load constant and a present position of the motor; estimating a car and counterweight load torque according to a car weight of the elevator car and a counterweight weight; estimating an interference torque according to the rope load torque and the car and counterweight load torque, and performing a feedforward compensation to the motor based on the interference torque.

Abstract: A fault detection method is used to determine whether a power switch coupled to a DC bus of a power conversion circuit is faulted. The method includes: detecting a bus voltage to provide a voltage signal and acquiring at least one detection value according to the voltage signal; providing control signals sequentially to turn off or turn on the power switch; determining that the power switch is a short-circuit fault if a first detection value is greater than or equal to a first threshold value when the power switch is turned off; determining that the power switch is an open-circuit fault if a second detection value is less than a second threshold value when the power switch is turned on; and providing an alarm signal or a disable signal when the power switch is the short-circuit fault or the open-circuit fault.

Abstract: Embodiments of the present disclosure provide a method and system for training a model by using training data. The training data includes a plurality of samples, each sample includes N features, and features in the plurality of samples form N feature columns, and the method includes: determining an importance value of each of the N feature columns; determining whether the importance value of each of the N feature columns satisfies a threshold condition; performing a dimension reduction on M feature columns to generate P feature columns in response to the determination that the importance values of the M feature columns do not satisfy the threshold condition, wherein M<N and P<M; merging (N?M) feature columns having importance values that satisfy the threshold condition and the generated P feature columns to obtain (N?M+P) feature columns; and training the model based on the training data including the (N?M+P) feature columns.

Abstract: Downhole tractor control systems and methods to adjust a load of a downhole motor to drive one or more wheels of the downhole tractor are disclosed. A method to adjust a load of a downhole motor includes receiving a user input of a desired speed and torque for a plurality of motors, where the plurality of motors powering rotation of wheels of a downhole tractor. The method also includes determining a minimum actual motor speed of the plurality of motors. For at least one motor of the plurality of motors, the method includes determining a power controller output and determining a torque controller output. The method further includes adjusting a voltage source invertor based on a lesser of the power controller output and the torque controller output to modulate voltage provided to the at least one motor.

Abstract: Downhole tractor control systems and methods to maintain a load among multiple tractors are disclosed. A method to adjust a load among multiple tractors includes receiving first power feedback of a first downhole tractor, receiving second power feedback of a second downhole tractor, identifying an unbalance load condition when a difference between the first power feedback and the second power feedback exceeds a predetermined threshold, and adjusting, in response to identifying the unbalance load condition and based on the difference, power reference of the first downhole tractor and the second downhole tractor.

Abstract: Downhole tractor control systems and methods to maintain a load of a downhole tractor are disclosed. A method to maintain a load of a downhole tractor includes identifying a reduction of power of a first set of motors of a plurality of motors of the downhole tractor, determining whether the reduction of power of the first set of motors is below a first threshold, and increasing, in response to the determination, a first power limit of a second set of motors of the plurality of motors to a maximum acceptable power limit of the second set of motors while maintaining the load of the downhole tractor.

Abstract: Downhole tractor control systems and methods to adjust a load of a downhole motor to drive one or more wheels of the downhole tractor are disclosed. A method to adjust a load of a downhole motor includes receiving a user input of a desired speed and torque for a plurality of motors, where the plurality of motors powering rotation of wheels of a downhole tractor. The method also includes determining a minimum actual motor speed of the plurality of motors. For at least one motor of the plurality of motors, the method includes determining a power controller output and determining a torque controller output. The method further includes adjusting a voltage source invertor based on a lesser of the power controller output and the torque controller output to modulate voltage provided to the at least one motor.

Abstract: A motor driving method includes steps of: at an open loop phase and in response to a motor being operated under a steady-state, calculating an angle difference between an estimation coordinate axis of the motor and an actual coordinate axis by a controller, according to an estimation voltage value, an estimation current value and at least one electrical parameter feedback from the motor and in reference with the estimation coordinate axis of the motor; calculating an actual current value in reference with the actual coordinate axis according to the angle difference by the controller; calculating a load torque estimation value associated with the motor according to the actual current value by the controller; and, in response to the open loop phase being switched to a close loop phase, compensating an output torque of the motor according to the load torque estimation value by the controller.

Abstract: A method for obtaining metallic carbon nanotubes is provided. An insulating substrate comprising hollow portions and non-hollow portions is provided. A plurality of electrodes is formed on a surface of the non-hollow portions. A plurality of carbon nanotubes is formed on a surface of the insulating substrate, and the carbon nanotubes stretch across the hollow portions. The insulating substrate, the plurality of electrodes and the carbon nanotubes are placed into a cavity, and the cavity is evacuated. A voltage is applied between any two electrodes, and photos of carbon nanotubes suspended between the two electrodes are taken. In the photo, darker ones are semiconducting carbon nanotubes, and brighter ones are metallic carbon nanotubes. Finally, the semiconducting carbon nanotubes are removed.

Abstract: A method for synchronizing downhole tractor and surface winch deployment includes inserting into a wellbore a tool string connected to a wireline, where the tool string includes a variable speed tractor. The method also includes deploying the tractor, and deploying the wireline from a winch. The method further includes dynamically monitoring, by a device disposed downhole, a wireline tension as an indicator of synchronization of the tractor and winch.

Abstract: An estimation method for estimating a rotor frequency of a motor during freewheeling, includes: applying a fixed input voltage and one selected from a plurality of stator frequencies to the motor sequentially so as to perform frequency scanning; detecting a stator current value of the motor corresponding to the selected stator frequency; calculating a stator current slope of the stator current values sequentially; defining a target period from a start point where the stator current slope varies from positive to negative to an end point where the stator current slope varies from negative to positive; and determining that a difference between the scanned stator frequency and the rotor frequency is within a preset value, then designating any of the corresponding stator frequencies during the target period as an estimated value of the rotor frequency.

Abstract: Data storage and calling methods and devices are provided. One of the methods includes: receiving first motion data and business data; establishing an association relationship between the first motion data and the business data and storing the association relationship; receiving second motion data; and determining first motion data that matches the second motion data, and returning, to a sender of the second motion data, business data associated with the matched first motion data.

Abstract: A motor driving method includes steps of: at an open loop phase and in response to a motor being operated under a steady-state, calculating an angle difference between an estimation coordinate axis of the motor and an actual coordinate axis by a controller, according to an estimation voltage value, an estimation current value and at least one electrical parameter feedback from the motor and in reference with the estimation coordinate axis of the motor; calculating an actual current value in reference with the actual coordinate axis according to the angle difference by the controller; calculating a load torque estimation value associated with the motor according to the actual current value by the controller; and, in response to the open loop phase being switched to a close loop phase, compensating an output torque of the motor according to the load torque estimation value by the controller.

Abstract: Data storage and calling methods and devices are provided. One of the methods includes: receiving first motion data and business data; establishing an association relationship between the first motion data and the business data and storing the association relationship; receiving second motion data; and determining first motion data that matches the second motion data, and returning, to a sender of the second motion data, business data associated with the matched first motion data.

Abstract: A fault detection method is used to determine whether a power switch coupled to a DC bus of a power conversion circuit is faulted. The method includes: detecting a bus voltage to provide a voltage signal and acquiring at least one detection value according to the voltage signal; providing control signals sequentially to turn off or turn on the power switch; determining that the power switch is a short-circuit fault if a first detection value is greater than or equal to a first threshold value when the power switch is turned off; determining that the power switch is an open-circuit fault if a second detection value is less than a second threshold value when the power switch is turned on; and providing an alarm signal or a disable signal when the power switch is the short-circuit fault or the open-circuit fault.

Abstract: Computer-implemented methods, computer-implemented systems, and non-transitory, computer-readable media for processing interaction sequence data are disclosed. One computer-implemented method includes: obtaining a dynamic interaction graph is obtained, where the dynamic interaction graph is constructed based on a dynamic interaction sequence, including a plurality of interactions arranged in a chronological order, where each interaction includes two objects involved in the interaction and a time of the interaction. In the dynamic interaction graph, a sub-graph corresponding to a target node is determined, where nodes in the sub-graph comprise the target node and connection nodes connected to the target node through a predetermined amount of edges originating from the target node. A feature vector corresponding to the target node is determined based on a node feature of each of the nodes of the sub-graph and directions of edges of the sub-graph.

Abstract: An information processing apparatus includes a receiving unit configured to receive, from a terminal of a delivery requester of a battery, a delivery request for a battery for which a delivery location of the battery is designated, a selecting unit configured to select at least one storage location of a battery, and a specifying unit configured to specify a deliverer who delivers the battery from a storage location. The specifying unit is configured to transmit a delivery inquiry including information of the delivery location and the storage location to a terminal of a delivery candidate, and specify the delivery candidate as the deliverer. When the selecting unit selects a plurality of storage locations for one delivery, the delivery inquiry includes information of each storage location.