54results about How to "High level of accuracy" patented technology

An electric vehicle incorporates a ground fault detecting system and has first and second ungrounded power supplies. The ground fault detecting system includes a first insulation resistance detector for detecting a first insulation resistance of the first ungrounded power supply with respect to a grounded region of the electric vehicle, and a second insulation resistance detector for detecting a second insulation resistance of the second ungrounded power supply with respect to the grounded region. The first insulation resistance detector and the second insulation resistance detector detect the first insulation resistance and the second insulation resistance at different times, respectively.

The invention discloses a field integral detecting system of a three-phase electric energy measuring system of an electric distribution network, which is mainly composed of a portable adjustable three-phase voltage and electric energy meter, an electric energy meter verifier, a three-phase active electric energy meter field measuring circuit and a three-phase active electric energy meter standard measuring circuit. According to a V-V connection method or a Y-Y connection method, a primary loop of a high-voltage current transformer of the field measuring circuit is connected with a standard high-voltage current transformer in series, and a voltage transformer loop of the field measuring circuit is connected with a standard voltage transformer in parallel. With the field integral detecting system of the three-phase electric energy measuring system of the electric distribution network, the comprehensive error is minimized, and the accuracy of the measuring device is improved by integral test. The system directly, truly and accurately measures the integral operating performance of the electric energy measuring system of a three-phase power supply system of the electric distribution network.

The invention discloses a combined container type gas flow detection device by the pVTt method. The gas flow detection device comprises two or more standard containers, a buffer container I, an intelligent collecting system and a control system. Each standard container is provided with an inlet end valve, a valve for combination and selection and an outlet end valve. Inlets of the outlet end valves serve as installation ports of detected flow meters. All the valves for combination and selection are mutually communicated. The outlet end valves are communicated with the buffer container I. The intelligent collecting system collects pressure p, temperature T and inflating time t in the standard containers before inflating and after inflating and pressure p, temperature T and inflating time t at installation ports of the detected flow meters. The control system is used for controlling all the valves to be opened or closed. According to the combined container type gas flow detection device by the pVTt method, the standard containers are adopted to be independently or randomly combined into different standard containers, and a working gas source and a pressure, temperature and time collecting system are shared. The range of detection flow is enlarged by more than 2n-1 times compared with a single container in the prior art, wherein n is the number of the containers. In this way, installation cost is greatly lowered, and detection efficiency is improved.

The invention relates to an induction voltage divider based method for judging detection error exception of a voltage transformer. According to a transformer error theory and an induction voltage divider theory, the method cascades an induction voltage divider and a standard voltage transformer to form a comparison standard voltage transformer in any transformation ratio for respectively comparing the errors of a voltage transformer to be tested and the standard voltage transformer so as to accurately judge exceptional error reasons occurring in the on-site detection process of the voltage transformer. The invention has the advantages of high accuracy grade, small size, portability, convenient judgment method, strong operability, low cost, high efficiency, scientific and accurate conclusion, and the like and is suitable for judging and processing the error exception in the detection process of the voltage transformer on site or in a laboratory.

A spectral color sensor including a spectroscopic unit that disperses reflected light from a measurement target, and a light detection element that detects the dispersed light from the reflected light, comprises: a storage unit that stores a correspondence relationship between a pre-measured wavelength of the dispersed light projected on the light detection element and a projection position, as well as a stray light component; a first correction unit that, based on a measurement result when a color is measured, corrects the correspondence relationship between the wavelength of the dispersed light projected on the light detection element and the projection position stored in the storage unit; and a second correction unit that carry out wavelength correction on the stray light component stored in the storage unit using the corrected correspondence relationship between the wavelength and the projection position.

In a process for producing leaves (20, 20′) for a leaf seal, in particular as a seal for a gas turbine, which leaves (20, 20′) are laterally delimited by a peripheral edge contour and have regions of different thicknesses (d1, d2), a simplification, without sacrificing precision, is achieved by virtue of the edge contour of the leaves (20, 20′) being cut out of a metal sheet (28) by an etching process and the regions of different thicknesses (d1, d2) also being produced simultaneously as part of the etching process.

In an injection system having a device for metering fuel into an exhaust system of a Diesel engine, and a method for controlling the injection of fuel into the exhaust system, wherein the injection system has a high-pressure pump which feeds fuel to an accumulator under high pressure and injectors which inject fuel from the accumulator into the combustion chambers of the internal combustion engine, a fuel spray nozzle arranged in the exhaust system is in communication with the injection system via a fuel metering unit including a control valve and a metering valve and a pressure regulating valve is arranged between the control valve and the metering valve for controlling the pressure of the fuel being metered by the metering valve for injection into the exhaust system via the spray nozzle.

The invention provides a high-precision current comparator, which comprises a current transformer assembly and an annular ampere turn balance indicator coaxially arranged in the center of the current transformer, wherein the current transformer assembly comprises a primary iron core, a secondary iron core coaxially arranged in the primary iron core, a corresponding primary winding, a secondary winding, a primary compensation winding and a secondary compensation winding; the ampere turn balance indicator comprises a measurement error compensation winding, a detection winding and a tertiary iron core; the tertiary iron core is arranged in an inner magnetic shielding piece; and the measurement error compensation winding is wound on the inner magnetic shielding piece. The high-precision current comparator provided by the invention has the advantages that influences from magnetic errors and capacitive errors can be reduced; the accuracy level of the current comparator is improved; the current comparator is applied to the highest standard in a self calibration system; the error accumulation value during a measurement downward transfer process can be reduced; the measurement accuracy of the current comparator self calibration system is enhanced; and the accurate application of the current comparator in the industry can be ensured.

A method of manufacturing an optical fiber of the invention includes: preparing a direction changer; drawing the bare optical fiber from an optical fiber preform; providing a coated layer on a periphery of the bare optical fiber; obtaining an optical fiber by curing the coated layer; changing a direction of the bare optical fiber at a position between a bare-optical-fiber formation position and a coated-layer provision position; and measuring the outer diameter of the coated layer; and adjusting the length of the bare optical fiber from a drawing unit to a coating unit by controlling a position of the direction changer based on a measurement value of the outer diameter, the drawing unit forming the bare optical fiber, the coating unit providing the coated layer on the periphery of the bare optical fiber.

The invention provides a high- and low-voltage hybrid excitation double-stage voltage transformer and a calibration method thereof. The double-stage voltage transformer comprises a main voltage transformer 1 and an auxiliary voltage transformer 2, wherein the main transformer 1 comprises a first-stage iron core I, a second-stage iron core II, a primary winding W1, a second winding W2, a high-voltage excitation winding W3 and a low-voltage excitation winding W4, the low-voltage excitation winding W4 and the high-voltage excitation winding W3 are sequentially wound around the first-stage iron core I, the second winding W2 and the primary winding W1 are sequentially wound after the first-stage iron core I and the second-stage iron core II are laminated, the auxiliary voltage transformer 2 is used for performing excitation on the main voltage transformer and comprises an iron core, an auxiliary primary winding W5, an auxiliary second winding W6 and a power supply winding W7, the auxiliary primary winding W5, the auxiliary second winding W6 and the power supply winding W7 are sequentially wound around the iron core, the auxiliary primary winding W5 is connected with the primary winding W1 and the high-voltage excitation winding W3 of the main voltage transformer, and the auxiliary secondary winding W6 is connected with the low-voltage excitation winding W4 of the main voltage transformer.

A columnar rod reference member made of a material whose coefficient of thermal expansion is different from a flight tube is placed in contact with the tube. One end of the tube and o the reference member are fixed to each other with a fixture part. A distance measurement sensor measures the difference in length between the tube and the reference member whose lengths fluctuate due to a change in temperature. A displacement of the difference in length, as expressed by a proportion, is larger than that of the length of the flight tube. The difference in length is far smaller than the length of the flight tube. This improves detection of the displacement due to thermal expansion with a strain gauge or sensor. The m / z values in mass spectrum data are corrected based on the measured values of the displacement, whereby a highly accurate mass discrepancy correction is achieved.

A method for measuring a windspeed vector is described. A true airspeed vector of a flying machine is measured while the machine is in flight using one or more nanowires on the flying machine. Each nanowire is configured to measure a value of local air velocity relative to the flying machine. A velocity of the flying machine relative to the ground is measured while the machine is in flight, and then (a) the true airspeed vector is subtracted from (b) the velocity of the flying machine relative to the ground. Other applications are also described.

A method, system, and computer program product is provided, for example, for assisting a user of the vehicle in following a prescribed speed limit while travelling in the vehicle. The method comprises providing a speed limit related recommendation to the user of the vehicle. The method further comprises receiving an image data representing a posted sign, in a vicinity of the vehicle, the image data being detected by one or more image capturing devices. Additionally, the method comprises processing the image data received to determine an observed numerical value. The method further comprises calculating, by a processor, a sign reliability factor based on a function of at least the observed numerical value, a historic mean of one or more vehicle speeds at the time of sign observation and a standard deviation of the one or more vehicle speeds at the time of sign observation. Additionally, the method may include providing data for an indication of the speed limit to be followed by the vehicle.

The invention discloses a rectangular Hall sensor array structure designing method for big direct current measurement. A round array structure is abandoned, and a Hall sensor array arranged in a rectangular mode is used; a high-order Simpson integration algorithm is adopted, the number of required Hall chips is decreased while the required measurement accuracy is reached, and the sensor manufacturing cost is reduced. By adopting the method, the accuracy and antijamming capability of Hall sensors are improved while the advantages of simple structure, low cost and the like of the Hall sensors are kept.

To widen the dynamic range of a dielectric barrier ionization detector (BID), an insertion length of a sample injection tube 16 into a second gas passage 11 is set so that a sample-gas ejection port 16a is located on the downstream side of a dilution gas from the upper edge of a collector electrode 14 at which a DC electric field concentrates. By this setting, although the detection sensitivity is lower than in the case where the sample-gas ejection port 16a is placed to maximize the detection sensitivity, the decrease in the detection sensitivity to high-concentration samples is reduced since absorption of light by the sample gas is alleviated. Consequently, the sample-concentration range with a linearly-changing sensitivity becomes wider than that of conventional BIDs. Although the detection sensitivity becomes lower than that of conventional BIDs, a detection sensitivity adequately higher than that of FIDs can be ensured.

The invention discloses a build-up force standard machine capable of realizing a self-checking function. The build-up force standard machine comprises an oil cylinder socket and a moving cross beam, wherein a 10MN standard sensor group is installed in the oil cylinder socket; an oil cylinder is installed on the oil cylinder socket; the top part of the oil cylinder is provided with a back cap, thebottom part is provided with a nut and a locking disc, a piston is arranged inside the oil cylinder, and the upper part of the back cap is connected with a lead screw; the moving cross beam is mountedon the upper part of the lead screw, an upper pressing plate is mounted at the center of the bottom part of the lead screw, and the center of the top part is provided with a speed reducer; and four minor chain wheels on the speed reducer are connected with corresponding large chain wheel by means of a chain or a belt; and a moving platform is arranged on the upper part of the oil cylinder socket,the moving platform comprises a linear guide rail and a workbench moving plate, the workbench moving plate is connected with a ball screw by means of a movable nut, the ball screw is connected with an output shaft of a servo motor, a workbench is mounted on the upper part of the workbench moving plate, a 3MN standard sensor group and a 1MN standard sensor group are arranged on the linear guide rail, and the 3MN standard sensor group and the 1MN standard sensor group are mounted on the same trolley moving assembly and are integrally connected with the workbench.

The invention discloses an air core coil mutual inductance coefficient error elimination method and application based on a rotation cancellation principle. The method comprises steps of enabling a rotating disc to rotate by 360 DEG / n relative to a current carrying lead, measuring a voltage of an air core coil, rotating the rotating disc by the same degree and measuring a voltage, and performing n times of rotation; obtaining mutual inductance coefficients according to voltage and current values; and performing weighted average of the mutual inductance coefficients to obtain the accurate mutual inductance coefficient value of the air core coil. The invention discloses an air core coil current measurement method. The air core coil mutual inductance coefficient error elimination method is used for obtaining the mutual inductance coefficient, the rotating disc is rotated at the same degree by many times to obtain multiple groups of voltages of the air core coil, currents are obtained according to the mutual inductance coefficients and the voltages, and the accurate value of a tested current is obtained by weighted average of the multiple groups of currents. Under a precondition that factors of the air core coil symmetry, the current carrying lead cross section, the tested current central position and the like are unknown, the instability of the mutual inductance coefficient is reduced, influences on currents can be eliminated, and the measurement accuracy of the air core coil is improved.

[Object] To extract a target region for a far-infrared image with a high level of accuracy.[Solution] Provided is an image processing device including: an adjustment unit that adjusts any one of a background image which is a far-infrared image showing a background that does not include an object and a target image which is a far-infrared image showing the object, on the basis of a time change model of an observation pixel value; and an extraction unit that extracts a target region including the object in the target image on the basis of a result of comparison between the background image and the target image after the adjustment is performed.

The invention relates to a contact-type applanation tonometer calibrating apparatus and method, and belongs to the field of tonometer detection. The contact-type applanation tonometer calibrating apparatus comprises a horizontal base, an electronic scale, a three-dimensional adjusting base and an L-shaped balance support; a fixing column and a horizontal installation table are arranged at the positions, close to the left edge and the right edge of the horizontal base, of the horizontal base respectively, the electronic scale is placed on the horizontal installation table, and the L-shaped balance support is placed on the fixing column and the electronic scale in a stretching-across mode; a door-shaped supporting table stretches across a horizontal rod of the L-shaped balance support, and the three-dimensional adjusting base is placed on the door-shaped supporting table. The L-shaped balance support is liner contact with the fixing column and is in point contact with the electronic scale, and a tonometer is calibrated according to the moment balance principle. By means of the contact-type applanation tonometer calibrating apparatus and method, the calibrating accuracy stage is high, and the good long-term stability and the good repeatability are achieved.

The invention provides a frozen current-based method and system for automatic identification of a topological relation of power distribution network courts. The method comprises the following steps: setting a frozen current transaction threshold value, judging whether current transaction exceeds the set threshold value or not, and if so, transmitting a freezing command to all low-voltage fault sensors in a broadcasting manner, and freezing current information at the same time; reading the current freezing data with timestamps of all the low-voltage fault sensors in sequence in a polling mode, calculating current freezing data and the last freezing data, and determining relevant parameters including current increment, harmonic increment and leakage current increment information; and performing data grouping and branch analysis according to the related parameters of the frozen current, performing hierarchical analysis according to different main and branch identification results, and determining a topological structure of the power distribution network courts. According to the invention, low-voltage topology automatic identification can be realized.

A capacitor inspection device includes a substrate made of an insulating material, a first conductor unit and a second conductor unit arranged on the substrate, a signal input unit and a signal output unit attached to the substrate, a network analyzer and a pressurizing unit. The network analyzer has an input port connected to the signal input unit and an output port connected to the signal output unit. The first and second conductor units make contact with an anode and a cathode of a capacitor, respectively. The pressurizing unit presses the anode of capacitor onto the first conductor unit and the cathode onto the second conductor unit.

The invention discloses a method for accurately calculating and analyzing harmonic and electric energy quality. The method comprises the following steps: selecting a detected signal sampling sequence; carrying out discrete Fourier transformation (DFT) on the sampling sequence; selecting a 3-order rapid attenuation window Nuttall; after windowing a signal, carrying out the discrete Fourier transformation; calculating to solve a phase phik; and finally, obtaining amplitude Ak, frequency fk and the phase phik of a detected signal to finish the analysis of the harmonic and the electric energy quality. According to the method, long-range leakage is eliminated by windowing, and an error, caused by the long-range leakage, is eliminated by using an interpolation algorithm; the frequency spectrum leakage caused by nonsynchronous sampling in the prior art is avoided by the method. A test comparing result shows that the frequency, amplitude and phase measurement errors of the algorithm are very small; compared with an actual measurement error, the errors can be completely ignored. With the adoption of the method, the equipment can be used as a harmonic measurement standard device capable of being used as a quality standard laboratory of a provincial-level technical supervision bureau or an electric power research institute and above.

The invention discloses a rotary decimal fine-tuning resistance box, which comprises a plurality of resistance trays and a trimming resistance tray, wherein the trimming resistance tray comprises a standard resistor RS, 10 auxiliary resistors RN with different resistance values, a moving contact and a fixed contact K, wherein the standard resistor RS is fixedly welded at an input end and an output end of a tray circuit; 10 auxiliary resistors RN are connected with the moving contact and the fixed contact K in series respectively and then connected with the standard resistor RS in parallel for output; indicating values of the auxiliary resistors RN are 0-10; and output values of the auxiliary resistors are 10, 11, ... ... 19 and 20. The rotary decimal fine-tuning resistance box can improve one or more accuracy grades; the digits, behind a decimal point, of the output value of the resistance box can be increased; the tenfold resolution is improved after increasing one digit; improvement can be carried out by an existing standard resistance box; additional capital investment is not needed; and the accuracy and the resolution of the whole standard resistance box are greatly improved.

A method includes: performing a time-frequency analysis on measurement data to obtain waveform data representing a temporal change in the intensity of each of a plurality of frequency components; dividing the waveform data of each of a plurality of predetermined frequencies into a plurality of segments so that each section where positive values successively occur and each section where negative values successively occur in a time-axis direction are defined as one segment; calculating the area of each of the segments to obtain segment values; creating, for the waveform data of each of the predetermined frequency components, a selected segment group by excluding a segment whose segment value exceeds a predetermined reference value from the segments in the waveform data; and determining a noise level of each of the predetermined frequency components based on the average value of the segment values of the segments included in the selected segment group.

The invention discloses a manufacturing method of a rotary type decimal fine turning resistor box. By utilizing an existing standard resistor box, a high-level panel without the need of adding a measurement panel is modified; the high-level panel is changed into a fine turning resistor panel; in a manufacturing process, all resistor elements of the high-level panel are detached and a standard resistor RS is welded at an input end and an output end of the high-level panel; auxiliary resistors RN which correspond to 10 different resistance values from 0 to 10 are connected into the panel in sequence respectively; after a movable contact and a static contact are connected with the auxiliary resistors RN in series, the movable contact and the static contact are connected with the standard resistor RS in parallel and are finally connected into a general circuit in series. According to the manufacturing method of the rotary type decimal fine turning resistor box, one or more than one accuracy grade of the fine turning resistor box can be improved; the digits of an output value of the resistor box after a decimal point are increased, and ten times of resolution can be improved when one digit is increased; the existing standard resistor box is used for modifying and extra capital investment is not needed.

The method generates a simulated object represented by finite elements each comprising two or more nodes that represent a first physical object, the first simulated object comprising a plurality of segments placed adjacent to each other to form a surface of the first simulated object. The method further includes generating a second simulated object. The method determines the distance between individual segments of the first simulated object and the plurality of segments of the second simulated object. The method determines a stiffness matrix and force vectors for the at least one segment of the first simulated object that is in contact with at least one segment of the second simulated object. The method transforms the stiffness matrix and the force vector from the segments to determine a stiffness matrix and a force vector on the two or more nodes of the finite element representation of the physical objects.

The invention discloses a low-voltage current transformer for metering supervision, which belongs to the technical field of electric measurement. The transformer comprises an iron core, a secondary winding and a magnetic conductive ring, the secondary winding is wound on the iron core, and the iron core wound with the secondary winding is solidified and placed in the magnetic conductive ring; andthe secondary winding is connected with an automatic verification system of the low-voltage current transformer for metering. The accuracy level of the device is higher than that of a common low-voltage current transformer and can reach 0.02 level or 0.05 level, and the device has good reproducibility, stability and lifting variation and can be used for intermediate check and quality monitoring ofthe automatic verification system of the low-voltage current transformer, so that the measurement process of the automatic verification system is always in a statistical control state.

A device (100) configured for the realization of a wire aerial of an element of radio frequency identification (RFID), which device (100) comprises:a main body (101), extending along a longitudinal direction (L) and adapted to be constrained to a support, which main body (101) has a longitudinal seat (112) adapted to house a wire for the realization of the aerial;a putting-wire head (150) arranged at one end of said main body (101) and constrained to the latter,said putting-wire head (150) comprising:a guide element (102), preferably rotatable according to an axis parallel to said longitudinal direction (L), which guide element (102) is adapted to engage the wire and to deposit it on a substrate and has a translational degree of freedom along said longitudinal direction (L) with respect to said main body (101);and a restraining element (103) of the wire, apt to selectively abut on said guide element (102) and preferably shaped like a beak,the overall arrangement being such that said putting-wire head (150) is apt to assume a first rest configuration, wherein said restraining element (103) is attested on said guide element (102) and the wire is retained between them, and a second operative configuration, wherein said restraining element (103) is spaced from said guide element (102) in such a way that the wire can slide within said seat (112) and be deposed on the substrate by means of said guide element (102).