183results about How to "Reduce asymmetry" patented technology

An intelligent parking space control system and method for a charging station, including an intelligent parking space lock, a station-level monitoring system, an operation monitoring system, and a client, the intelligent parking space lock including a power supply, a vehicle detection and acquisition device, a communication device, a main control device, and a motion control device, sound and light alarm device. The advantages of the present invention are: the vehicle attributes can be identified through the vehicle detection and acquisition device, and the station-level monitoring system can automatically identify and warn electric vehicles that do not need to be charged or have been fully charged, which can significantly improve the utilization rate of charging parking spaces. The operation monitoring system provides information to the client, and can share the information of the charging parking space of the charging station itself for users to query, so that users can find the optimal charging parking space and its location, and reduce the asymmetry of supply and demand information of charging parking spaces.

A sound capture device comprises a symmetric microphone array that includes non-radially-oriented directional sensors (101). The device typically derives a spherical harmonic representation of the incident sound field, and affords higher signal-to-noise ratios and better directional fidelity than prior arrays, across a wide range of audio frequencies.

The invention discloses an automatic intelligent power distribution system and a power distribution method. The power distribution system comprises a power distribution executing unit, and the power distribution executing unit receives a power distribution command from a power distribution monitoring terminal and gates a corresponding phase line on a three-phase power transmission line to a single-phase power supply line on an output side of the power distribution executing unit to achieve intelligent power distribution. According to the automatic intelligent power distribution system, low-voltage three-phase disequilibrium distribution on an input side of a single-phase user is achieved through the power distribution executing unit on an input side of an electricity meter of the single-phase user, the power distribution monitoring terminal receives the electrical load information of each single-phase user in a wireless or power line carrier communication mode, and a basis is provided for the equilibrium distribution of single-phase user quantity on each phase line of the three-phase power transmission line on the whole; the power distribution monitoring terminal sends the power distribution command to the power distribution executing unit and the power distribution executing unit enables each single-phase user to be connected to a corresponding power supply phase line in a grouping mode, and therefore equilibrium power distribution is achieved for single-phase users on a low-voltage side.

The invention provides a digital credit authentication method which i=is used for identifying a potential credit risk of a credit subject and comprises the following steps: a, reading identity information of the credit subject, b, inquiring a credit record according to the identity information, c, carrying out identification evaluation according to the credit record, d, generating a credit evaluation level identification and a credit evaluation report according to an identification evaluation result, and e, pushing the identification evaluation result in real time. According to the other aspect of the invention, the invention further provides a digital credit authentication processing device. Various evaluation work can be effectively handled by an evaluation index system, an evaluation algorithm and an evaluation processing device, and the accuracy and efficiency are improved in conjunction with arrangement of expert database.

An apparatus, system, and method are disclosed for mitigating signal asymmetry. An analog to digital converter samples an analog signal from a read head and converts the sample to a digital input signal. The digital input signal addresses a look-up module, and the look-up module outputs a modified digital signal. The modified digital signal value is a specified function of the digital input signal value, wherein the specified function is configured to mitigate the asymmetry of the digital input signal. The modified digital signal value may be periodically recalculated to adjust for read head wear.

The invention discloses a self-maintained friction stir welding method with reversely rotating upper and lower shaft shoulders, and relates to a self-maintained friction stir welding method to solve the problems that: the upper and lower shaft shoulders have unequal diameters but rotate in the same direction with equal speed, and in the welding process, the weld heat input is large, a workpiece is easy to deform, a mixing needle is inclined to fracture, and the distribution of a weld zone temperature field, a joint structure and residual stress are asymmetric, so that the joint performance is asymmetric, and the bearing capacity of a welding structure is reduced. The method comprises the following steps of: 1, determining the size of a stirring head, namely determining the diameter of the upper shaft shoulder, the stirring needle and the lower shaft shoulder according to the thickness of a first welded workpiece and a second welded workpiece; 2, determining the use length of the stirring needle; 3, fixing the first welded workpiece and the second welded workpiece; 4, positioning the stirring head; and 5, performing friction stir welding on the first welded workpiece and the second welded workpiece, namely integrally forming the upper shaft shoulder and the stirring needle, and allowing the lower shaft shoulder and the upper shaft shoulder to rotate in opposite directions. The self-maintained friction stir welding method is used for self-maintained friction stir welding.

A novel power unit of a cascade unit comprises a DC voltage driver unit, a voltage lifting chopping part and an inverting part. The DC voltage drive of the power unit adopts a three-phase bridge type uncontrolled rectifier system, and two controllable IGBTs and two fast diodes are added at the DC side, thus forming a DC voltage lifting chopping circuit which can control the voltage at the DC link and broaden the scope of AC output voltage amplitude; an inverter adopts IGBT single-phase full bridge controllable output, and a fault bypass circuit is added at the output terminal of the inverter; and a rectifier transformer is of common wiring multi-winding type, and all secondary windings have the same wiring mode. A voltage lifting half-bridge and a neutral point in a filter capacitor set are connected with the neutral point in a harmonic current circuit to provide a channel for injecting zero sequence current so as to achieve the sinusoid of high power factor rectification and the input current.

A magnetic sensing element which allows a high reproduction output and reduction in asymmetry of reproduction waveform to become mutually compatible, as well as a method for manufacturing the same, is provided. In the inside of a second pinned magnetic layer and a free magnetic layer, the atomic percentage of an element Z is decreased in a region close to a non-magnetic material layer. Consequently, the ferromagnetic coupling magnetic field due to magnetostatic coupling (topological coupling) between the pinned magnetic layer and the free magnetic layer can be reduced. At the same time, in a region at a distance from the non-magnetic material layer, the atomic percentage of an element Z is increased, a spin-dependent bulk scattering coefficient is increased, and a product of the amount of change in magnetic resistance and the element area of the magnetic sensing element can be maintained at a high level.

A liquid crystal display device includes a liquid crystal cell, first and second polarizers disposed outside the liquid crystal cell, first and second retardation plates arranged between the first and second polarizers, and the liquid crystal cell, and optical layers arranged between the first and second retardation plates and the liquid crystal cell. The first and second retardation plates have lagging axes perpendicular with each other. The first polarizer has an absorption axis inclining by about 45 degrees relative to the lagging axis of the first retardation plate, and inclining by about 90 degrees relative to an absorption axis of the second polarizer. The absorption axes of the first and second polarizers are angularly deviated such that characteristic of a viewing angle in the liquid crystal display device is rendered symmetric, relative to a symmetry axis about which liquid crystal is aligned in different directions.

The invention relates to an optical fiber ring capable of eliminating influence of external environmental factors, and belongs to the technical field of optical measurement and optical fiber sensing. The optical fiber ring comprises a main body formed by winding an optical fiber, and is characterized by further comprising a heat-insulating layer, an optical fiber ring framework and a magnetic shielding material layer, wherein the heat-insulating layer is coated on the surface of the main body and is used for eliminating influence of external factors; the optical fiber ring framework is made of a non-metallic material and is used for being matched with a thermal expansion coefficient of the optical fiber, so that when the outside temperature changes, the accuracy deviation of an optical fiber gyroscope caused by equivalent asymmetry degree due to temperature change of the optical fiber ring can be reduced; and the magnetic shielding material layer is arranged outside the optical fiber ring so as to reduce or eliminate the influence of an external magnetic field on an angle sensor of the optical fiber ring.

The invention discloses a condenser with a liquid separation type spiral tube structure, which belongs to the technical fields of heat exchange and heat transfer. A spiral heat exchange tube is fixed in a shell of the condenser with the liquid separation type spiral tube structure; a liquid guiding tube is distributed on the outer circumference of the spiral heat exchange tube; the upper end of the spiral heat exchange tube is a condensing working substance inlet tube; the lower end of the spiral heat exchange tube is a condensing working substance outlet tube; the upper end of the outer circumference of the shell is a cooling water outlet; and the lower end of the outer circumference of the shell is a cooling water inlet. In a condensing process, a thick liquid film distributed on the side wall surface of the spiral outer circumference is derived in a non-dynamical way by utilizing the combined action of surface tension, capillary force and centrifugal force; a thin liquid film is promoted to transfer heat in a condensation phase change process; and the heat resistance of a condensed liquid film on the side of the outer circumference of a spiral tube is decreased, thereby obviously improving the heat exchange performance on the side of a condensation phase change tube. By using the condenser with the liquid separation type efficient spiral tube, a condensate liquid is separated mainly by means of the centrifugal force and the capillary force without being influenced by gravity, and the condensation heat exchange coefficient can be obviously improved both in a ground environment or a microgravity environment.

The invention relates to an emergency supply unit (1) with a ram-air turbine (2) which can be driven by an air stream (14) and with an energy converter (4) for at least partly maintaining the functioning of a hydraulic system and/or electrical system on board an aircraft in an emergency situation, wherein the energy converter (4) can be driven by means of the ram-air turbine (2) and the emergency supply unit (1) can selectively be brought into a standby mode or into an operating mode.; According to the invention, at least the ram-air turbine (2) is surrounded substantially concentrically by a casing (5) forming a flow channel (6) and the energy converter (4) is directly coupled to the ram-air turbine (2) via a drive shaft (3) and the air stream (14) can be delivered to the ram-air turbine (2) through at least one air inlet (9, 17, 18), wherein the spatial position of the ram-air turbine (2) remains substantially unchanged when changing between the standby mode and the operating mode. The integration of the ram-air turbine (2) into the flow channel (6) results in a very compact and space-saving design of the emergency supply unit (1) according to the invention, thus offering a plurality of additional installation options, for example in the region of the landing flap rail covering (8) below a wing (7) of an aircraft.; Moreover, the substantially completely encapsulated formation of the emergency supply unit (1) without a pivot arm and with direct coupling of the ram-air turbine (2) to the energy converter (4) through the drive shaft (3) is structurally simple and therefore permits largely maintenance-free operation with greater fail safety.

The invention discloses a method for reactive power control of voltage unbalance sudden rise of a double-feed wind generator set power network. The method is characterized by comprising the following steps: 1, decoupling positive and negative sequences of the voltage of a stator of a double-feed motor; 2, calculating the reactive current of the stator; 3, calculating the proportion of positive sequence reactive power in total reactive power; 4, calculating and synthesizing a current instruction value of a rotor; and 5, performing closed-loop control on the current of the rotor. By adopting the method disclosed by the invention, the distribution of the stator current and positive and negative sequence reactive power can be controlled, thereby achieving a target of performing compound control on the degree of asymmetry of generator terminal voltage and reactive power ripple rejection.